Merge branch 'ported-moebius'

50 files changed, 2260 insertions, 83 deletions

diff --git a/layout/base/nsLayoutDebugger.cpp b/layout/base/nsLayoutDebugger.cpp
index 22c313c72..6ce629bc9 100644
--- a/layout/base/nsLayoutDebugger.cpp
+++ b/layout/base/nsLayoutDebugger.cpp
@@ -126,8 +126,10 @@ PrintDisplayItemTo(nsDisplayListBuilder* aBuilder, nsDisplayItem* aItem,
       contentData.AppendLiteral(" id:");
       contentData.Append(tmp);
     }
-    if (content->GetClasses()) {
-      content->GetClasses()->ToString(tmp);
+    const nsAttrValue* classes = content->IsElement() ?
+      content->AsElement()->GetClasses() : nullptr;
+    if (classes) {
+      classes->ToString(tmp);
       contentData.AppendLiteral(" class:");
       contentData.Append(tmp);
     }
diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp
index 789c91f50..c8c91b251 100644
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -4637,6 +4637,63 @@ GetPercentBSize(const nsStyleCoord& aStyle,
   return true;
 }
 
+// Return true if aStyle can be resolved to a definite value and if so
+// return that value in aResult.
+static bool
+GetDefiniteSize(const nsStyleCoord&       aStyle,
+                nsIFrame*                 aFrame,
+                bool                      aIsInlineAxis,
+                const Maybe<LogicalSize>& aPercentageBasis,
+                nscoord*                  aResult)
+{
+  switch (aStyle.GetUnit()) {
+    case eStyleUnit_Coord:
+      *aResult = aStyle.GetCoordValue();
+      return true;
+    case eStyleUnit_Percent: {
+      if (aPercentageBasis.isNothing()) {
+        return false;
+      }
+      auto wm = aFrame->GetWritingMode();
+      nscoord pb = aIsInlineAxis ? aPercentageBasis.value().ISize(wm)
+                                 : aPercentageBasis.value().BSize(wm);
+      if (pb != NS_UNCONSTRAINEDSIZE) {
+        nscoord p = NSToCoordFloorClamped(pb * aStyle.GetPercentValue());
+        *aResult = std::max(nscoord(0), p);
+        return true;
+      }
+      return false;
+    }
+    case eStyleUnit_Calc: {
+      nsStyleCoord::Calc* calc = aStyle.GetCalcValue();
+      if (calc->mPercent != 0.0f) {
+        if (aPercentageBasis.isNothing()) {
+          return false;
+        }
+        auto wm = aFrame->GetWritingMode();
+        nscoord pb = aIsInlineAxis ? aPercentageBasis.value().ISize(wm)
+                                   : aPercentageBasis.value().BSize(wm);
+        if (pb == NS_UNCONSTRAINEDSIZE) {
+          // XXXmats given that we're calculating an intrinsic size here,
+          // maybe we should back-compute the calc-size using AddPercents?
+          return false;
+        }
+        *aResult = std::max(0, calc->mLength +
+                               NSToCoordFloorClamped(pb * calc->mPercent));
+      } else {
+        *aResult = std::max(0, calc->mLength);
+      }
+      return true;
+    }
+    default:
+      return false;
+  }
+}
+
+//
+// NOTE: this function will be replaced by GetDefiniteSizeTakenByBoxSizing (bug 1363918).
+// Please do not add new uses of this function.
+//
 // Get the amount of vertical space taken out of aFrame's content area due to
 // its borders and paddings given the box-sizing value in aBoxSizing.  We don't
 // get aBoxSizing from the frame because some callers want to compute this for
@@ -4681,6 +4738,54 @@ GetBSizeTakenByBoxSizing(StyleBoxSizing aBoxSizing,
   return bSizeTakenByBoxSizing;
 }
 
+// Get the amount of space taken out of aFrame's content area due to its
+// borders and paddings given the box-sizing value in aBoxSizing.  We don't
+// get aBoxSizing from the frame because some callers want to compute this for
+// specific box-sizing values.
+// aIsInlineAxis is true if we're computing for aFrame's inline axis.
+// aIgnorePadding is true if padding should be ignored.
+static nscoord
+GetDefiniteSizeTakenByBoxSizing(StyleBoxSizing aBoxSizing,
+                                nsIFrame* aFrame,
+                                bool aIsInlineAxis,
+                                bool aIgnorePadding,
+                                const Maybe<LogicalSize>& aPercentageBasis)
+{
+  nscoord sizeTakenByBoxSizing = 0;
+  if (MOZ_UNLIKELY(aBoxSizing == StyleBoxSizing::Border)) {
+    const bool isHorizontalAxis =
+      aIsInlineAxis == !aFrame->GetWritingMode().IsVertical();
+    const nsStyleBorder* styleBorder = aFrame->StyleBorder();
+    sizeTakenByBoxSizing =
+      isHorizontalAxis ? styleBorder->GetComputedBorder().LeftRight()
+                       : styleBorder->GetComputedBorder().TopBottom();
+    if (!aIgnorePadding) {
+      const nsStyleSides& stylePadding = aFrame->StylePadding()->mPadding;
+      const nsStyleCoord& pStart =
+        stylePadding.Get(isHorizontalAxis ? eSideLeft : eSideTop);
+      const nsStyleCoord& pEnd =
+        stylePadding.Get(isHorizontalAxis ? eSideRight : eSideBottom);
+      nscoord pad;
+      // XXXbz Calling GetPercentBSize on padding values looks bogus, since
+      // percent padding is always a percentage of the inline-size of the
+      // containing block.  We should perhaps just treat non-absolute paddings
+      // here as 0 instead, except that in some cases the width may in fact be
+      // known.  See bug 1231059.
+      if (GetDefiniteSize(pStart, aFrame, aIsInlineAxis, aPercentageBasis, &pad) ||
+          (aPercentageBasis.isNothing() &&
+           GetPercentBSize(pStart, aFrame, isHorizontalAxis, pad))) {
+        sizeTakenByBoxSizing += pad;
+      }
+      if (GetDefiniteSize(pEnd, aFrame, aIsInlineAxis, aPercentageBasis, &pad) ||
+          (aPercentageBasis.isNothing() &&
+           GetPercentBSize(pEnd, aFrame, isHorizontalAxis, pad))) {
+        sizeTakenByBoxSizing += pad;
+      }
+    }
+  }
+  return sizeTakenByBoxSizing;
+}
+
 // Handles only -moz-max-content and -moz-min-content, and
 // -moz-fit-content for min-width and max-width, since the others
 // (-moz-fit-content for width, and -moz-available) have no effect on
@@ -4940,17 +5045,21 @@ AddStateBitToAncestors(nsIFrame* aFrame, nsFrameState aBit)
 }
 
 /* static */ nscoord
-nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
-                                nsRenderingContext* aRenderingContext,
-                                nsIFrame*           aFrame,
-                                IntrinsicISizeType  aType,
-                                uint32_t            aFlags,
-                                nscoord             aMarginBoxMinSizeClamp)
+nsLayoutUtils::IntrinsicForAxis(PhysicalAxis              aAxis,
+                                nsRenderingContext*       aRenderingContext,
+                                nsIFrame*                 aFrame,
+                                IntrinsicISizeType        aType,
+                                const Maybe<LogicalSize>& aPercentageBasis,
+                                uint32_t                  aFlags,
+                                nscoord                   aMarginBoxMinSizeClamp)
 {
   NS_PRECONDITION(aFrame, "null frame");
   NS_PRECONDITION(aFrame->GetParent(),
                   "IntrinsicForAxis called on frame not in tree");
   NS_PRECONDITION(aType == MIN_ISIZE || aType == PREF_ISIZE, "bad type");
+  MOZ_ASSERT(aFrame->GetParent()->Type() != LayoutFrameType::GridContainer ||
+             aPercentageBasis.isSome(),
+             "grid layout should always pass a percentage basis");
 
   const bool horizontalAxis = MOZ_LIKELY(aAxis == eAxisHorizontal);
 #ifdef DEBUG_INTRINSIC_WIDTH
@@ -5014,6 +5123,7 @@ nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
 
   PhysicalAxis ourInlineAxis =
     aFrame->GetWritingMode().PhysicalAxis(eLogicalAxisInline);
+  const bool isInlineAxis = aAxis == ourInlineAxis;
   // If we have a specified width (or a specified 'min-width' greater
   // than the specified 'max-width', which works out to the same thing),
   // don't even bother getting the frame's intrinsic width, because in
@@ -5043,7 +5153,7 @@ nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
       // constraint is the max-content contribution which we shouldn't clamp.
       aMarginBoxMinSizeClamp = NS_MAXSIZE;
     }
-    if (MOZ_UNLIKELY(aAxis != ourInlineAxis)) {
+    if (MOZ_UNLIKELY(!isInlineAxis)) {
       IntrinsicSize intrinsicSize = aFrame->GetIntrinsicSize();
       const nsStyleCoord intrinsicBCoord =
         horizontalAxis ? intrinsicSize.width : intrinsicSize.height;
@@ -5105,21 +5215,23 @@ nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
             NS_FRAME_DESCENDANT_INTRINSIC_ISIZE_DEPENDS_ON_BSIZE);
 
         nscoord bSizeTakenByBoxSizing =
-          GetBSizeTakenByBoxSizing(boxSizing, aFrame, horizontalAxis,
-                                   aFlags & IGNORE_PADDING);
-
+          GetDefiniteSizeTakenByBoxSizing(boxSizing, aFrame, !isInlineAxis,
+                                          aFlags & IGNORE_PADDING,
+                                          aPercentageBasis);
         // NOTE: This is only the minContentSize if we've been passed MIN_INTRINSIC_ISIZE
         // (which is fine, because this should only be used inside a check for that flag).
         nscoord minContentSize = result;
         nscoord h;
-        if (GetAbsoluteCoord(styleBSize, h) ||
-            GetPercentBSize(styleBSize, aFrame, horizontalAxis, h)) {
+        if (GetDefiniteSize(styleBSize, aFrame, !isInlineAxis, aPercentageBasis, &h) ||
+            (aPercentageBasis.isNothing() &&
+             GetPercentBSize(styleBSize, aFrame, horizontalAxis, h))) {
           h = std::max(0, h - bSizeTakenByBoxSizing);
           result = NSCoordMulDiv(h, ratioISize, ratioBSize);
         }
 
-        if (GetAbsoluteCoord(styleMaxBSize, h) ||
-            GetPercentBSize(styleMaxBSize, aFrame, horizontalAxis, h)) {
+        if (GetDefiniteSize(styleMaxBSize, aFrame, !isInlineAxis, aPercentageBasis, &h) ||
+            (aPercentageBasis.isNothing() &&
+             GetPercentBSize(styleMaxBSize, aFrame, horizontalAxis, h))) {
           h = std::max(0, h - bSizeTakenByBoxSizing);
           nscoord maxISize = NSCoordMulDiv(h, ratioISize, ratioBSize);
           if (maxISize < result) {
@@ -5130,8 +5242,9 @@ nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
           }
         }
 
-        if (GetAbsoluteCoord(styleMinBSize, h) ||
-            GetPercentBSize(styleMinBSize, aFrame, horizontalAxis, h)) {
+        if (GetDefiniteSize(styleMinBSize, aFrame, !isInlineAxis, aPercentageBasis, &h) ||
+            (aPercentageBasis.isNothing() &&
+             GetPercentBSize(styleMinBSize, aFrame, horizontalAxis, h))) {
           h = std::max(0, h - bSizeTakenByBoxSizing);
           nscoord minISize = NSCoordMulDiv(h, ratioISize, ratioBSize);
           if (minISize > result) {
@@ -5158,8 +5271,8 @@ nsLayoutUtils::IntrinsicForAxis(PhysicalAxis        aAxis,
   }
 
   nsIFrame::IntrinsicISizeOffsetData offsets =
-    MOZ_LIKELY(aAxis == ourInlineAxis) ? aFrame->IntrinsicISizeOffsets()
-                                       : aFrame->IntrinsicBSizeOffsets();
+    MOZ_LIKELY(isInlineAxis) ? aFrame->IntrinsicISizeOffsets()
+                             : aFrame->IntrinsicBSizeOffsets();
   nscoord contentBoxSize = result;
   result = AddIntrinsicSizeOffset(aRenderingContext, aFrame, offsets, aType,
                                   boxSizing, result, min, styleISize,
@@ -5196,7 +5309,7 @@ nsLayoutUtils::IntrinsicForContainer(nsRenderingContext* aRenderingContext,
   // We want the size aFrame will contribute to its parent's inline-size.
   PhysicalAxis axis =
     aFrame->GetParent()->GetWritingMode().PhysicalAxis(eLogicalAxisInline);
-  return IntrinsicForAxis(axis, aRenderingContext, aFrame, aType, aFlags);
+  return IntrinsicForAxis(axis, aRenderingContext, aFrame, aType, Nothing(), aFlags);
 }
 
 /* static */ nscoord
diff --git a/layout/base/nsLayoutUtils.h b/layout/base/nsLayoutUtils.h
index d9580a3df..97fc410b0 100644
--- a/layout/base/nsLayoutUtils.h
+++ b/layout/base/nsLayoutUtils.h
@@ -1378,6 +1378,10 @@ public:
    * width, its 'width', 'min-width', and 'max-width' properties (or 'height'
    * variations if that's what matches aAxis) and its padding, border and margin
    * in the corresponding dimension.
+   * @param aPercentageBasis an optional percentage basis (in aFrame's WM).
+   *   Pass NS_UNCONSTRAINEDSIZE if the basis is indefinite in either/both axes.
+   *   If you pass Nothing() a percentage basis will be calculated from aFrame's
+   *   ancestors' computed size in the relevant axis, if needed.
    * @param aMarginBoxMinSizeClamp make the result fit within this margin-box
    * size by reducing the *content size* (flooring at zero).  This is used for:
    * https://drafts.csswg.org/css-grid/#min-size-auto
@@ -1396,6 +1400,7 @@ public:
                    nsRenderingContext*   aRenderingContext,
                    nsIFrame*             aFrame,
                    IntrinsicISizeType    aType,
+                   const mozilla::Maybe<mozilla::LogicalSize>& aPercentageBasis = mozilla::Nothing(),
                    uint32_t              aFlags = 0,
                    nscoord               aMarginBoxMinSizeClamp = NS_MAXSIZE);
   /**
diff --git a/layout/forms/nsFieldSetFrame.cpp b/layout/forms/nsFieldSetFrame.cpp
index befd41ee2..fc9f0571b 100644
--- a/layout/forms/nsFieldSetFrame.cpp
+++ b/layout/forms/nsFieldSetFrame.cpp
@@ -5,26 +5,22 @@
 
 #include "nsFieldSetFrame.h"
 
+#include <algorithm>
 #include "mozilla/gfx/2D.h"
+#include "mozilla/Likely.h"
+#include "mozilla/Maybe.h"
 #include "nsCSSAnonBoxes.h"
-#include "nsLayoutUtils.h"
-#include "nsLegendFrame.h"
 #include "nsCSSRendering.h"
-#include <algorithm>
-#include "nsIFrame.h"
-#include "nsPresContext.h"
-#include "mozilla/RestyleManager.h"
-#include "nsGkAtoms.h"
-#include "nsStyleConsts.h"
 #include "nsDisplayList.h"
+#include "nsGkAtoms.h"
+#include "nsIFrameInlines.h"
+#include "nsLayoutUtils.h"
+#include "nsLegendFrame.h"
 #include "nsRenderingContext.h"
-#include "nsIScrollableFrame.h"
-#include "mozilla/Likely.h"
-#include "mozilla/Maybe.h"
+#include "nsStyleConsts.h"
 
 using namespace mozilla;
 using namespace mozilla::gfx;
-using namespace mozilla::image;
 using namespace mozilla::layout;
 
 nsContainerFrame*
@@ -126,7 +122,7 @@ void
 nsDisplayFieldSetBorderBackground::Paint(nsDisplayListBuilder* aBuilder,
                                          nsRenderingContext* aCtx)
 {
-  DrawResult result = static_cast<nsFieldSetFrame*>(mFrame)->
+  image::DrawResult result = static_cast<nsFieldSetFrame*>(mFrame)->
     PaintBorder(aBuilder, *aCtx, ToReferenceFrame(), mVisibleRect);
 
   nsDisplayItemGenericImageGeometry::UpdateDrawResult(this, result);
@@ -210,7 +206,7 @@ nsFieldSetFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
   contentDisplayItems.MoveTo(aLists);
 }
 
-DrawResult
+image::DrawResult
 nsFieldSetFrame::PaintBorder(
   nsDisplayListBuilder* aBuilder,
   nsRenderingContext& aRenderingContext,
@@ -695,9 +691,50 @@ nsFieldSetFrame::AccessibleType()
 #endif
 
 nscoord
-nsFieldSetFrame::GetLogicalBaseline(WritingMode aWritingMode) const
+nsFieldSetFrame::GetLogicalBaseline(WritingMode aWM) const
+{
+  switch (StyleDisplay()->mDisplay) {
+    case mozilla::StyleDisplay::Grid:
+    case mozilla::StyleDisplay::InlineGrid:
+    case mozilla::StyleDisplay::Flex:
+    case mozilla::StyleDisplay::InlineFlex:
+      return BaselineBOffset(aWM, BaselineSharingGroup::eFirst,
+                             AlignmentContext::eInline);
+    default:
+      return BSize(aWM) - BaselineBOffset(aWM, BaselineSharingGroup::eLast,
+                                          AlignmentContext::eInline);
+  }
+}
+
+bool
+nsFieldSetFrame::GetVerticalAlignBaseline(WritingMode aWM,
+                                          nscoord* aBaseline) const
 {
   nsIFrame* inner = GetInner();
-  return inner->BStart(aWritingMode, GetParent()->GetSize()) +
-    inner->GetLogicalBaseline(aWritingMode);
+  MOZ_ASSERT(!inner->GetWritingMode().IsOrthogonalTo(aWM));
+  if (!inner->GetVerticalAlignBaseline(aWM, aBaseline)) {
+    return false;
+  }
+  nscoord innerBStart = inner->BStart(aWM, GetSize());
+  *aBaseline += innerBStart;
+  return true;
+}
+
+bool
+nsFieldSetFrame::GetNaturalBaselineBOffset(WritingMode          aWM,
+                                           BaselineSharingGroup aBaselineGroup,
+                                           nscoord*             aBaseline) const
+{
+  nsIFrame* inner = GetInner();
+  MOZ_ASSERT(!inner->GetWritingMode().IsOrthogonalTo(aWM));
+  if (!inner->GetNaturalBaselineBOffset(aWM, aBaselineGroup, aBaseline)) {
+    return false;
+  }
+  nscoord innerBStart = inner->BStart(aWM, GetSize());
+  if (aBaselineGroup == BaselineSharingGroup::eFirst) {
+    *aBaseline += innerBStart;
+  } else {
+    *aBaseline += BSize(aWM) - (innerBStart + inner->BSize(aWM));
+  }
+  return true;
 }
diff --git a/layout/forms/nsFieldSetFrame.h b/layout/forms/nsFieldSetFrame.h
index 54eaf678f..5eb67c320 100644
--- a/layout/forms/nsFieldSetFrame.h
+++ b/layout/forms/nsFieldSetFrame.h
@@ -7,7 +7,7 @@
 #define nsFieldSetFrame_h___
 
 #include "mozilla/Attributes.h"
-#include "imgIContainer.h"
+#include "DrawResult.h"
 #include "nsContainerFrame.h"
 
 class nsFieldSetFrame final : public nsContainerFrame
@@ -33,7 +33,6 @@ public:
               const mozilla::LogicalSize& aBorder,
               const mozilla::LogicalSize& aPadding,
               ComputeSizeFlags aFlags) override;
-  virtual nscoord GetLogicalBaseline(mozilla::WritingMode aWritingMode) const override;
 
   /**
    * The area to paint box-shadows around.  It's the border rect except
@@ -46,6 +45,13 @@ public:
                       const ReflowInput& aReflowInput,
                       nsReflowStatus&          aStatus) override;
                                
+  nscoord GetLogicalBaseline(mozilla::WritingMode aWM) const override;
+  bool GetVerticalAlignBaseline(mozilla::WritingMode aWM,
+                                nscoord* aBaseline) const override;
+  bool GetNaturalBaselineBOffset(mozilla::WritingMode aWM,
+                                 BaselineSharingGroup aBaselineGroup,
+                                 nscoord* aBaseline) const override;
+
   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                 const nsRect&           aDirtyRect,
                                 const nsDisplayListSet& aLists) override;
diff --git a/layout/forms/nsHTMLButtonControlFrame.cpp b/layout/forms/nsHTMLButtonControlFrame.cpp
index ef9459ef2..2e4fa9f67 100644
--- a/layout/forms/nsHTMLButtonControlFrame.cpp
+++ b/layout/forms/nsHTMLButtonControlFrame.cpp
@@ -418,6 +418,47 @@ nsHTMLButtonControlFrame::ReflowButtonContents(nsPresContext* aPresContext,
   aButtonDesiredSize.SetOverflowAreasToDesiredBounds();
 }
 
+bool
+nsHTMLButtonControlFrame::GetVerticalAlignBaseline(mozilla::WritingMode aWM,
+                                                   nscoord* aBaseline) const
+{
+  nsIFrame* inner = mFrames.FirstChild();
+  if (MOZ_UNLIKELY(inner->GetWritingMode().IsOrthogonalTo(aWM))) {
+    return false;
+  }
+  if (!inner->GetVerticalAlignBaseline(aWM, aBaseline)) {
+    // <input type=color> has an empty block frame as inner frame
+    *aBaseline = inner->
+      SynthesizeBaselineBOffsetFromBorderBox(aWM, BaselineSharingGroup::eFirst);
+  }
+  nscoord innerBStart = inner->BStart(aWM, GetSize());
+  *aBaseline += innerBStart;
+  return true;
+}
+
+bool
+nsHTMLButtonControlFrame::GetNaturalBaselineBOffset(mozilla::WritingMode aWM,
+                                         BaselineSharingGroup aBaselineGroup,
+                                         nscoord* aBaseline) const
+{
+  nsIFrame* inner = mFrames.FirstChild();
+  if (MOZ_UNLIKELY(inner->GetWritingMode().IsOrthogonalTo(aWM))) {
+    return false;
+  }
+  if (!inner->GetNaturalBaselineBOffset(aWM, aBaselineGroup, aBaseline)) {
+    // <input type=color> has an empty block frame as inner frame
+    *aBaseline = inner->
+      SynthesizeBaselineBOffsetFromBorderBox(aWM, aBaselineGroup);
+  }
+  nscoord innerBStart = inner->BStart(aWM, GetSize());
+  if (aBaselineGroup == BaselineSharingGroup::eFirst) {
+    *aBaseline += innerBStart;
+  } else {
+    *aBaseline += BSize(aWM) - (innerBStart + inner->BSize(aWM));
+  }
+  return true;
+}
+
 nsresult nsHTMLButtonControlFrame::SetFormProperty(nsIAtom* aName, const nsAString& aValue)
 {
   if (nsGkAtoms::value == aName) {
diff --git a/layout/forms/nsHTMLButtonControlFrame.h b/layout/forms/nsHTMLButtonControlFrame.h
index 96ad0f366..432afa12c 100644
--- a/layout/forms/nsHTMLButtonControlFrame.h
+++ b/layout/forms/nsHTMLButtonControlFrame.h
@@ -39,6 +39,13 @@ public:
                       const ReflowInput& aReflowInput,
                       nsReflowStatus&          aStatus) override;
 
+  bool GetVerticalAlignBaseline(mozilla::WritingMode aWM,
+                                nscoord* aBaseline) const override;
+
+  bool GetNaturalBaselineBOffset(mozilla::WritingMode aWM,
+                                 BaselineSharingGroup aBaselineGroup,
+                                 nscoord* aBaseline) const override;
+
   virtual nsresult HandleEvent(nsPresContext* aPresContext, 
                                mozilla::WidgetGUIEvent* aEvent,
                                nsEventStatus* aEventStatus) override;
diff --git a/layout/forms/nsLegendFrame.h b/layout/forms/nsLegendFrame.h
index 5f5e1e03e..a9e11cbbe 100644
--- a/layout/forms/nsLegendFrame.h
+++ b/layout/forms/nsLegendFrame.h
@@ -9,7 +9,8 @@
 #include "mozilla/Attributes.h"
 #include "nsBlockFrame.h"
 
-class nsLegendFrame : public nsBlockFrame {
+class nsLegendFrame final : public nsBlockFrame
+{
 public:
   NS_DECL_QUERYFRAME_TARGET(nsLegendFrame)
   NS_DECL_QUERYFRAME
@@ -30,7 +31,7 @@ public:
   virtual nsresult GetFrameName(nsAString& aResult) const override;
 #endif
 
-  int32_t GetLogicalAlign(WritingMode aCBWM);
+  int32_t GetLogicalAlign(mozilla::WritingMode aCBWM);
 };
 
 
diff --git a/layout/forms/nsTextControlFrame.cpp b/layout/forms/nsTextControlFrame.cpp
index f85bc2a80..a7f7d40a8 100644
--- a/layout/forms/nsTextControlFrame.cpp
+++ b/layout/forms/nsTextControlFrame.cpp
@@ -106,6 +106,7 @@ private:
 
 nsTextControlFrame::nsTextControlFrame(nsStyleContext* aContext)
   : nsContainerFrame(aContext)
+  , mFirstBaseline(NS_INTRINSIC_WIDTH_UNKNOWN)
   , mEditorHasBeenInitialized(false)
   , mIsProcessing(false)
 #ifdef DEBUG
@@ -538,20 +539,20 @@ nsTextControlFrame::Reflow(nsPresContext*   aPresContext,
               aReflowInput.ComputedLogicalBorderPadding().BStartEnd(wm));
   aDesiredSize.SetSize(wm, finalSize);
 
-  // computation of the ascent wrt the input height
+  // Calculate the baseline and store it in mFirstBaseline.
   nscoord lineHeight = aReflowInput.ComputedBSize();
   float inflation = nsLayoutUtils::FontSizeInflationFor(this);
   if (!IsSingleLineTextControl()) {
     lineHeight = ReflowInput::CalcLineHeight(GetContent(), StyleContext(),
-                                                   NS_AUTOHEIGHT, inflation);
+                                             NS_AUTOHEIGHT, inflation);
   }
   RefPtr<nsFontMetrics> fontMet =
     nsLayoutUtils::GetFontMetricsForFrame(this, inflation);
-  // now adjust for our borders and padding
-  aDesiredSize.SetBlockStartAscent(
+  mFirstBaseline =
     nsLayoutUtils::GetCenteredFontBaseline(fontMet, lineHeight,
                                            wm.IsLineInverted()) +
-    aReflowInput.ComputedLogicalBorderPadding().BStart(wm));
+    aReflowInput.ComputedLogicalBorderPadding().BStart(wm);
+  aDesiredSize.SetBlockStartAscent(mFirstBaseline);
 
   // overflow handling
   aDesiredSize.SetOverflowAreasToDesiredBounds();
diff --git a/layout/forms/nsTextControlFrame.h b/layout/forms/nsTextControlFrame.h
index a76cba514..9d4d0b77c 100644
--- a/layout/forms/nsTextControlFrame.h
+++ b/layout/forms/nsTextControlFrame.h
@@ -62,6 +62,29 @@ public:
                       const ReflowInput& aReflowInput,
                       nsReflowStatus&          aStatus) override;
 
+  bool GetVerticalAlignBaseline(mozilla::WritingMode aWM,
+                                nscoord* aBaseline) const override
+  {
+    return GetNaturalBaselineBOffset(aWM, BaselineSharingGroup::eFirst, aBaseline);
+  }
+
+  bool GetNaturalBaselineBOffset(mozilla::WritingMode aWM,
+                                 BaselineSharingGroup aBaselineGroup,
+                                 nscoord* aBaseline) const override
+  {
+    if (!IsSingleLineTextControl()) {
+      return false;
+    }
+    NS_ASSERTION(mFirstBaseline != NS_INTRINSIC_WIDTH_UNKNOWN,
+                 "please call Reflow before asking for the baseline");
+    if (aBaselineGroup == BaselineSharingGroup::eFirst) {
+      *aBaseline = mFirstBaseline;
+    } else {
+      *aBaseline = BSize(aWM) - mFirstBaseline;
+    }
+    return true;
+  }
+
   virtual nsSize GetXULMinSize(nsBoxLayoutState& aBoxLayoutState) override;
   virtual bool IsXULCollapsed() override;
 
@@ -87,6 +110,14 @@ public:
       ~(nsIFrame::eReplaced | nsIFrame::eReplacedContainsBlock));
   }
 
+#ifdef DEBUG
+  void MarkIntrinsicISizesDirty() override
+  {
+    // Need another Reflow to have a correct baseline value again.
+    mFirstBaseline = NS_INTRINSIC_WIDTH_UNKNOWN;
+  }
+#endif
+
   // nsIAnonymousContentCreator
   virtual nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) override;
   virtual void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
@@ -300,6 +331,10 @@ private:
   }
 
 private:
+  // Our first baseline, or NS_INTRINSIC_WIDTH_UNKNOWN if we have a pending
+  // Reflow.
+  nscoord mFirstBaseline;
+
   // these packed bools could instead use the high order bits on mState, saving 4 bytes 
   bool mEditorHasBeenInitialized;
   bool mIsProcessing;
diff --git a/layout/generic/ReflowInput.cpp b/layout/generic/ReflowInput.cpp
index 42f4a24b5..a8756cea2 100644
--- a/layout/generic/ReflowInput.cpp
+++ b/layout/generic/ReflowInput.cpp
@@ -93,6 +93,9 @@ ReflowInput::ReflowInput(nsPresContext*       aPresContext,
   if (aFlags & B_CLAMP_MARGIN_BOX_MIN_SIZE) {
     mFlags.mBClampMarginBoxMinSize = true;
   }
+  if (aFlags & I_APPLY_AUTO_MIN_SIZE) {
+    mFlags.mApplyAutoMinSize = true;
+  }
 
   if (!(aFlags & CALLER_WILL_INIT)) {
     Init(aPresContext);
@@ -242,6 +245,7 @@ ReflowInput::ReflowInput(
   mFlags.mIOffsetsNeedCSSAlign = mFlags.mBOffsetsNeedCSSAlign = false;
   mFlags.mIClampMarginBoxMinSize = !!(aFlags & I_CLAMP_MARGIN_BOX_MIN_SIZE);
   mFlags.mBClampMarginBoxMinSize = !!(aFlags & B_CLAMP_MARGIN_BOX_MIN_SIZE);
+  mFlags.mApplyAutoMinSize = !!(aFlags & I_APPLY_AUTO_MIN_SIZE);
 
   mDiscoveredClearance = nullptr;
   mPercentBSizeObserver = (aParentReflowInput.mPercentBSizeObserver &&
@@ -1662,6 +1666,10 @@ ReflowInput::InitAbsoluteConstraints(nsPresContext* aPresContext,
     computeSizeFlags = ComputeSizeFlags(computeSizeFlags |
                          ComputeSizeFlags::eBClampMarginBoxMinSize);
   }
+  if (mFlags.mApplyAutoMinSize) {
+    computeSizeFlags = ComputeSizeFlags(computeSizeFlags |
+                         ComputeSizeFlags::eIApplyAutoMinSize);
+  }
   if (mFlags.mShrinkWrap) {
     computeSizeFlags =
       ComputeSizeFlags(computeSizeFlags | ComputeSizeFlags::eShrinkWrap);
@@ -2375,6 +2383,10 @@ ReflowInput::InitConstraints(nsPresContext*     aPresContext,
         computeSizeFlags = ComputeSizeFlags(computeSizeFlags |
                              ComputeSizeFlags::eBClampMarginBoxMinSize);
       }
+      if (mFlags.mApplyAutoMinSize) {
+        computeSizeFlags = ComputeSizeFlags(computeSizeFlags |
+                             ComputeSizeFlags::eIApplyAutoMinSize);
+      }
       if (mFlags.mShrinkWrap) {
         computeSizeFlags =
           ComputeSizeFlags(computeSizeFlags | ComputeSizeFlags::eShrinkWrap);
diff --git a/layout/generic/ReflowInput.h b/layout/generic/ReflowInput.h
index e42508646..09c980b72 100644
--- a/layout/generic/ReflowInput.h
+++ b/layout/generic/ReflowInput.h
@@ -220,6 +220,7 @@ public:
     uint32_t mStaticPosIsCBOrigin:1; // the STATIC_POS_IS_CB_ORIGIN ctor flag
     uint32_t mIClampMarginBoxMinSize:1; // the I_CLAMP_MARGIN_BOX_MIN_SIZE ctor flag
     uint32_t mBClampMarginBoxMinSize:1; // the B_CLAMP_MARGIN_BOX_MIN_SIZE ctor flag
+    uint32_t mApplyAutoMinSize : 1;       // the I_APPLY_AUTO_MIN_SIZE ctor flag
 
     // If set, the following two flags indicate that:
     // (1) this frame is absolutely-positioned (or fixed-positioned).
@@ -738,6 +739,9 @@ public:
 
     // Pass ComputeSizeFlags::eBClampMarginBoxMinSize to ComputeSize().
     B_CLAMP_MARGIN_BOX_MIN_SIZE = (1<<6),
+
+    // Pass ComputeSizeFlags::eIApplyAutoMinSize to ComputeSize().
+    I_APPLY_AUTO_MIN_SIZE = (1<<7),
   };
 
   // This method initializes various data members. It is automatically
diff --git a/layout/generic/nsFrame.cpp b/layout/generic/nsFrame.cpp
index 69791d5c5..418fa16b7 100644
--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -4781,7 +4781,7 @@ nsFrame::ComputeSize(nsRenderingContext* aRenderingContext,
       ComputeISizeValue(aRenderingContext, aCBSize.ISize(aWM),
                         boxSizingAdjust.ISize(aWM), boxSizingToMarginEdgeISize,
                         minISizeCoord, aFlags);
-  } else if (MOZ_UNLIKELY(isGridItem)) {
+  } else if (MOZ_UNLIKELY(aFlags & eIApplyAutoMinSize)) {
     // This implements "Implied Minimum Size of Grid Items".
     // https://drafts.csswg.org/css-grid/#min-size-auto
     minISize = std::min(maxISize, GetMinISize(aRenderingContext));
diff --git a/layout/generic/nsGridContainerFrame.cpp b/layout/generic/nsGridContainerFrame.cpp
index 71d5bba21..8f117b5ab 100644
--- a/layout/generic/nsGridContainerFrame.cpp
+++ b/layout/generic/nsGridContainerFrame.cpp
@@ -818,8 +818,11 @@ struct nsGridContainerFrame::GridItemInfo
     // Ditto *-content:[last ]baseline. Mutually exclusive w. eSelfBaseline.
     eContentBaseline =       0x10,
     eAllBaselineBits = eIsBaselineAligned | eSelfBaseline | eContentBaseline,
+    // Should apply Automatic Minimum Size per:
+    // https://drafts.csswg.org/css-grid/#min-size-auto
+    eApplyAutoMinSize =      0x20,
     // Clamp per https://drafts.csswg.org/css-grid/#min-size-auto
-    eClampMarginBoxMinSize = 0x20,
+    eClampMarginBoxMinSize = 0x40,
   };
 
   explicit GridItemInfo(nsIFrame* aFrame,
@@ -851,11 +854,11 @@ struct nsGridContainerFrame::GridItemInfo
     return aAlign;
   }
 
-  // Return true if we should we clamp this item's Automatic Minimum Size.
+  // Return true if we should apply Automatic Minimum Size to this item.
   // https://drafts.csswg.org/css-grid/#min-size-auto
-  bool ShouldClampMinSize(WritingMode aContainerWM,
-                          LogicalAxis aContainerAxis,
-                          nscoord aPercentageBasis) const
+  bool ShouldApplyAutoMinSize(WritingMode aContainerWM,
+                              LogicalAxis aContainerAxis,
+                              nscoord aPercentageBasis) const
   {
     const auto pos = mFrame->StylePosition();
     const auto& size = aContainerAxis == eLogicalAxisInline ?
@@ -2090,6 +2093,18 @@ struct MOZ_STACK_CLASS nsGridContainerFrame::GridReflowInput
                            SizingConstraint   aConstraint);
 
   /**
+   * Return the percentage basis for a grid item in its writing-mode.
+   * If aAxis is eLogicalAxisInline then we return NS_UNCONSTRAINEDSIZE in
+   * both axes since we know all track sizes are indefinite at this point
+   * (we calculate column sizes before row sizes).  Otherwise, assert that
+   * column sizes are known and calculate the size for aGridItem.mArea.mCols
+   * and use NS_UNCONSTRAINEDSIZE in the other axis.
+   * @param aAxis the axis we're currently calculating track sizes for
+   */
+  LogicalSize PercentageBasisFor(LogicalAxis aAxis,
+                                 const GridItemInfo& aGridItem) const;
+
+  /**
    * Return the containing block for a grid item occupying aArea.
    */
   LogicalRect ContainingBlockFor(const GridArea& aArea) const;
@@ -3731,18 +3746,20 @@ MeasuringReflow(nsIFrame*           aChild,
  * the child's margin-box) in aAxis.
  */
 static nscoord
-ContentContribution(const GridItemInfo&    aGridItem,
-                    const GridReflowInput& aState,
-                    nsRenderingContext*    aRC,
-                    WritingMode            aCBWM,
-                    LogicalAxis            aAxis,
-                    IntrinsicISizeType     aConstraint,
-                    nscoord                aMinSizeClamp = NS_MAXSIZE,
-                    uint32_t               aFlags = 0)
+ContentContribution(const GridItemInfo&       aGridItem,
+                    const GridReflowInput&    aState,
+                    nsRenderingContext*       aRC,
+                    WritingMode               aCBWM,
+                    LogicalAxis               aAxis,
+                    const Maybe<LogicalSize>& aPercentageBasis,
+                    IntrinsicISizeType        aConstraint,
+                    nscoord                   aMinSizeClamp = NS_MAXSIZE,
+                    uint32_t                  aFlags = 0)
 {
   nsIFrame* child = aGridItem.mFrame;
   PhysicalAxis axis(aCBWM.PhysicalAxis(aAxis));
   nscoord size = nsLayoutUtils::IntrinsicForAxis(axis, aRC, child, aConstraint,
+                   aPercentageBasis,
                    aFlags | nsLayoutUtils::BAIL_IF_REFLOW_NEEDED |
                             nsLayoutUtils::ADD_PERCENTS,
                    aMinSizeClamp);
@@ -3812,6 +3829,10 @@ struct CachedIntrinsicSizes
   Maybe<nscoord> mMinSize;
   Maybe<nscoord> mMinContentContribution;
   Maybe<nscoord> mMaxContentContribution;
+
+  // The item's percentage basis for intrinsic sizing purposes.
+  Maybe<LogicalSize> mPercentageBasis;
+
   // "if the grid item spans only grid tracks that have a fixed max track
   // sizing function, its automatic minimum size in that dimension is
   // further clamped to less than or equal to the size necessary to fit its
@@ -3832,7 +3853,11 @@ MinContentContribution(const GridItemInfo&    aGridItem,
   if (aCache->mMinContentContribution.isSome()) {
     return aCache->mMinContentContribution.value();
   }
+  if (aCache->mPercentageBasis.isNothing()) {
+    aCache->mPercentageBasis.emplace(aState.PercentageBasisFor(aAxis, aGridItem));
+  }
   nscoord s = ContentContribution(aGridItem, aState, aRC, aCBWM, aAxis,
+                                  aCache->mPercentageBasis,
                                   nsLayoutUtils::MIN_ISIZE,
                                   aCache->mMinSizeClamp);
   aCache->mMinContentContribution.emplace(s);
@@ -3850,7 +3875,11 @@ MaxContentContribution(const GridItemInfo&    aGridItem,
   if (aCache->mMaxContentContribution.isSome()) {
     return aCache->mMaxContentContribution.value();
   }
+  if (aCache->mPercentageBasis.isNothing()) {
+    aCache->mPercentageBasis.emplace(aState.PercentageBasisFor(aAxis, aGridItem));
+  }
   nscoord s = ContentContribution(aGridItem, aState, aRC, aCBWM, aAxis,
+                                  aCache->mPercentageBasis,
                                   nsLayoutUtils::PREF_ISIZE,
                                   aCache->mMinSizeClamp);
   aCache->mMaxContentContribution.emplace(s);
@@ -3904,7 +3933,11 @@ MinSize(const GridItemInfo&    aGridItem,
        child->StyleDisplay()->mOverflowX == NS_STYLE_OVERFLOW_VISIBLE)) {
     // Now calculate the "content size" part and return whichever is smaller.
     MOZ_ASSERT(unit != eStyleUnit_Enumerated || sz == NS_UNCONSTRAINEDSIZE);
+    if (aCache->mPercentageBasis.isNothing()) {
+      aCache->mPercentageBasis.emplace(aState.PercentageBasisFor(aAxis, aGridItem));
+    }
     sz = std::min(sz, ContentContribution(aGridItem, aState, aRC, aCBWM, aAxis,
+                                          aCache->mPercentageBasis,
                                           nsLayoutUtils::MIN_ISIZE,
                                           aCache->mMinSizeClamp,
                                           nsLayoutUtils::MIN_INTRINSIC_ISIZE));
@@ -3977,9 +4010,9 @@ nsGridContainerFrame::Tracks::ResolveIntrinsicSizeStep1(
   WritingMode wm = aState.mWM;
   // Calculate data for "Automatic Minimum Size" clamping, if needed.
   bool needed = ((sz.mState & TrackSize::eIntrinsicMinSizing) ||
-                 aConstraint == SizingConstraint::eNoConstraint);
-  if (needed && TrackSize::IsDefiniteMaxSizing(sz.mState) &&
-      aGridItem.ShouldClampMinSize(wm, mAxis, aPercentageBasis)) {
+                 aConstraint == SizingConstraint::eNoConstraint) &&
+                (aGridItem.mState[mAxis] & ItemState::eApplyAutoMinSize);
+  if (needed && TrackSize::IsDefiniteMaxSizing(sz.mState)) {
     if (sz.mState & TrackSize::eIntrinsicMinSizing) {
       auto maxCoord = aFunctions.MaxSizingFor(aRange.mStart);
       cache.mMinSizeClamp =
@@ -4382,6 +4415,14 @@ nsGridContainerFrame::Tracks::ResolveIntrinsicSize(
   iter.Reset();
   for (; !iter.AtEnd(); iter.Next()) {
     auto& gridItem = aGridItems[iter.GridItemIndex()];
+
+    // Check if we need to apply "Automatic Minimum Size" and cache it.
+    MOZ_ASSERT(!(gridItem.mState[mAxis] & ItemState::eApplyAutoMinSize),
+               "Why is eApplyAutoMinSize set already?");
+    if (gridItem.ShouldApplyAutoMinSize(wm, mAxis, aPercentageBasis)) {
+      gridItem.mState[mAxis] |= ItemState::eApplyAutoMinSize;
+    }
+
     const GridArea& area = gridItem.mArea;
     const LineRange& lineRange = area.*aRange;
     uint32_t span = lineRange.Extent();
@@ -4407,9 +4448,9 @@ nsGridContainerFrame::Tracks::ResolveIntrinsicSize(
         CachedIntrinsicSizes cache;
         // Calculate data for "Automatic Minimum Size" clamping, if needed.
         bool needed = ((state & TrackSize::eIntrinsicMinSizing) ||
-                       aConstraint == SizingConstraint::eNoConstraint);
-        if (needed && TrackSize::IsDefiniteMaxSizing(state) &&
-            gridItem.ShouldClampMinSize(wm, mAxis, aPercentageBasis)) {
+                       aConstraint == SizingConstraint::eNoConstraint) &&
+                      (gridItem.mState[mAxis] & ItemState::eApplyAutoMinSize);
+        if (needed && TrackSize::IsDefiniteMaxSizing(state)) {
           nscoord minSizeClamp = 0;
           for (auto i = lineRange.mStart, end = lineRange.mEnd; i < end; ++i) {
             auto maxCoord = aFunctions.MaxSizingFor(i);
@@ -4445,11 +4486,14 @@ nsGridContainerFrame::Tracks::ResolveIntrinsicSize(
           gridItem.mState[mAxis] |= ItemState::eIsFlexing;
         } else if (aConstraint == SizingConstraint::eNoConstraint &&
                    TrackSize::IsDefiniteMaxSizing(state) &&
-                   gridItem.ShouldClampMinSize(wm, mAxis, aPercentageBasis)) {
+                   (gridItem.mState[mAxis] & ItemState::eApplyAutoMinSize)) {
           gridItem.mState[mAxis] |= ItemState::eClampMarginBoxMinSize;
         }
       }
     }
+    MOZ_ASSERT(!(gridItem.mState[mAxis] & ItemState::eClampMarginBoxMinSize) ||
+               (gridItem.mState[mAxis] & ItemState::eApplyAutoMinSize),
+               "clamping only applies to Automatic Minimum Size");
   }
 
   // Step 2.
@@ -4707,7 +4751,8 @@ nsGridContainerFrame::Tracks::FindUsedFlexFraction(
     const GridItemInfo& item = aGridItems[iter.GridItemIndex()];
     if (item.mState[mAxis] & ItemState::eIsFlexing) {
       // XXX optimize: bug 1194446
-      nscoord spaceToFill = ContentContribution(item, aState, rc, wm, mAxis,
+      auto pb = Some(aState.PercentageBasisFor(mAxis, item));
+      nscoord spaceToFill = ContentContribution(item, aState, rc, wm, mAxis, pb,
                                                 nsLayoutUtils::PREF_ISIZE);
       if (spaceToFill <= 0) {
         continue;
@@ -5038,6 +5083,25 @@ nsGridContainerFrame::LineRange::ToPositionAndLengthForAbsPos(
   }
 }
 
+LogicalSize
+nsGridContainerFrame::GridReflowInput::PercentageBasisFor(
+  LogicalAxis aAxis,
+  const GridItemInfo& aGridItem) const
+{
+  auto wm = aGridItem.mFrame->GetWritingMode();
+  if (aAxis == eLogicalAxisInline) {
+    return LogicalSize(wm, NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
+  }
+  // Note: for now, we only resolve transferred percentages to row sizing.
+  // We may need to adjust these assertions once we implement bug 1300366.
+  MOZ_ASSERT(mCols.mCanResolveLineRangeSize);
+  MOZ_ASSERT(!mRows.mCanResolveLineRangeSize);
+  nscoord colSize = aGridItem.mArea.mCols.ToLength(mCols.mSizes);
+  nscoord rowSize = NS_UNCONSTRAINEDSIZE;
+  return !wm.IsOrthogonalTo(mWM) ?
+    LogicalSize(wm, colSize, rowSize) : LogicalSize(wm, rowSize, colSize);
+}
+
 LogicalRect
 nsGridContainerFrame::GridReflowInput::ContainingBlockFor(const GridArea& aArea) const
 {
@@ -5231,6 +5295,9 @@ nsGridContainerFrame::ReflowInFlowChild(nsIFrame*              aChild,
     } else {
       aChild->Properties().Delete(BClampMarginBoxMinSizeProperty());
     }
+    if ((aGridItemInfo->mState[childIAxis] & ItemState::eApplyAutoMinSize)) {
+      flags |= ReflowInput::I_APPLY_AUTO_MIN_SIZE;
+    }
   }
 
   if (!isConstrainedBSize) {
diff --git a/layout/generic/nsIFrame.h b/layout/generic/nsIFrame.h
index 50eb958e0..2acafa882 100644
--- a/layout/generic/nsIFrame.h
+++ b/layout/generic/nsIFrame.h
@@ -2105,6 +2105,14 @@ public:
      */
     eIClampMarginBoxMinSize = 1 << 2, // clamp in our inline axis
     eBClampMarginBoxMinSize = 1 << 3, // clamp in our block axis
+    /**
+     * The frame is stretching (per CSS Box Alignment) and doesn't have an
+     * Automatic Minimum Size in the indicated axis.
+     * (may be used for both flex/grid items, but currently only used for Grid)
+     * https://drafts.csswg.org/css-grid/#min-size-auto
+     * https://drafts.csswg.org/css-align-3/#valdef-justify-self-stretch
+     */
+    eIApplyAutoMinSize = 1 << 4, // only has an effect when eShrinkWrap is false
   };
 
   /**
diff --git a/layout/reftests/bugs/315920-17.html b/layout/reftests/bugs/315920-17.html
index 1681754a5..6d9180144 100644
--- a/layout/reftests/bugs/315920-17.html
+++ b/layout/reftests/bugs/315920-17.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html class="reftest-wait">
   <head>
     <style>
       input ~ label {color: red}
@@ -8,9 +8,7 @@
       input:checked:default + label {color: green}
     </style>
   </head>
-  <body onload='document.getElementById("two").setAttribute("checked", "true");
-                document.getElementById("one").setAttribute("checked", "checked");
-                document.getElementById("two").removeAttribute("checked");'>
+  <body>
     <form>
       <input type="checkbox" name="group1" id="one" value="1"/>
       <label for="one">Should be no red</label><br>
@@ -19,5 +17,14 @@
       <input type="checkbox" name="group1" id="three" value="3"/>
       <label for="three">Should be no red</label>
     </form>
+<script>
+function doTest() {
+  document.getElementById("two").setAttribute("checked", "true");
+  document.getElementById("one").setAttribute("checked", "checked");
+  document.getElementById("two").removeAttribute("checked");
+  setTimeout(function () { document.documentElement.removeAttribute("class"); }, 0);
+}
+window.addEventListener("MozReftestInvalidate", doTest);
+</script>
   </body>
 </html>
diff --git a/layout/reftests/css-grid/grid-auto-min-sizing-min-content-min-size-004-ref.html b/layout/reftests/css-grid/grid-auto-min-sizing-min-content-min-size-004-ref.html
index fc74cd214..caef8b031 100644
--- a/layout/reftests/css-grid/grid-auto-min-sizing-min-content-min-size-004-ref.html
+++ b/layout/reftests/css-grid/grid-auto-min-sizing-min-content-min-size-004-ref.html
@@ -36,7 +36,7 @@ var rowtest = [
 "min-width:80%; max-height:20px", "min-width:50%", "margin-left: 50px; width:50%"
 ];
 var results = [
-"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "24px/2px", "20px/2px", "20px/2px", "24px/2px", "24px/52px"
+"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "12px/2px", "20px/2px", "20px/2px", "24px/2px", "24px/52px"
 ];
 var item_height = [
 "0", "0", "0", "0", "0", "0", "12px", "20px", "20px", "24px", "312px"
diff --git a/layout/reftests/css-grid/grid-auto-min-sizing-transferred-size-004-ref.html b/layout/reftests/css-grid/grid-auto-min-sizing-transferred-size-004-ref.html
index c5d8a68ff..36a2d4920 100644
--- a/layout/reftests/css-grid/grid-auto-min-sizing-transferred-size-004-ref.html
+++ b/layout/reftests/css-grid/grid-auto-min-sizing-transferred-size-004-ref.html
@@ -36,7 +36,7 @@ var rowtest = [
 "min-width:80%; max-height:20px", "min-width:50%", "margin-left: 50px; width:50%"
 ];
 var results = [
-"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "24px/2px", "20px/2px", "20px/2px", "24px/2px", "24px/52px"
+"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "12px/2px", "20px/2px", "20px/2px", "24px/2px", "24px/52px"
 ];
 var item_height = [
 "0", "0", "0", "0", "0", "0", "12px", "20px", "20px", "24px", "312px"
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-001-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-001-ref.html
new file mode 100644
index 000000000..463bbb4e6
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-001-ref.html
@@ -0,0 +1,78 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: stretching overflow!=visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px 30px 3px / 7px 80px 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  min-width:0;
+  min-height:0;
+  box-sizing: border-box;
+}
+
+.oa, .os, .oh { width:80px; height:30px; }
+.m.oa, .m.os, .m.oh { width:70px; height:24px; }
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  " style="width:112px"><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   " style="width:112px"><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  " style="height:112px"><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   " style="height:112px"><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-001.html b/layout/reftests/css-grid/grid-item-overflow-stretch-001.html
new file mode 100644
index 000000000..4f6259abe
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-001.html
@@ -0,0 +1,74 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: stretching overflow!=visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-001-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+}
+
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-002-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-002-ref.html
new file mode 100644
index 000000000..a9690a54e
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-002-ref.html
@@ -0,0 +1,79 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: stretching overflow!=visible vertical-rl items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px 30px 3px / 7px 80px 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  writing-mode: vertical-rl;
+  min-width:0;
+  min-height:0;
+  box-sizing: border-box;
+}
+
+.oa, .os, .oh { width:80px; height:30px; }
+.m.oa, .m.os, .m.oh { width:70px; height:24px; }
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  " style="width:112px"><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   " style="width:112px"><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  " style="height:112px"><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   " style="height:112px"><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-002.html b/layout/reftests/css-grid/grid-item-overflow-stretch-002.html
new file mode 100644
index 000000000..520eed911
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-002.html
@@ -0,0 +1,75 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: stretching overflow!=visible vertical-rl items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-002-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  writing-mode: vertical-rl;
+}
+
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-003-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-003-ref.html
new file mode 100644
index 000000000..c082e6be4
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-003-ref.html
@@ -0,0 +1,84 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: margin:auto stretch items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px 30px 3px / 7px 112px 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+.c2 { grid-template-columns: 7px 122px 3px; }
+.h > .grid { grid: 7px 112px 3px / 7px 80px 3px; }
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  margin: 0 auto;
+  justify-self:start;
+  align-self:start;
+  height:28px;
+}
+.c2 > * { height:22px; }
+.h .grid > * {
+  margin: 10px 0 0 10px;
+  justify-self:center;
+  align-self:center;
+  width:5px;
+  height:110px;
+}
+
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid c2"><span class="m oa"><x></x></span></div>
+<div class="grid c2"><span class="m os"><x></x></span></div>
+<div class="grid c2"><span class="m oh"><x></x></span></div>
+<div class="grid c2"><span class="m   "><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-003.html b/layout/reftests/css-grid/grid-item-overflow-stretch-003.html
new file mode 100644
index 000000000..8bcd79d9b
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-003.html
@@ -0,0 +1,75 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: margin:auto stretch items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-003-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  margin: 0 auto;
+}
+.h .grid > * {
+  margin: auto;
+}
+
+.m  { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="oa"><x></x></span></div>
+<div class="grid"><span class="os"><x></x></span></div>
+<div class="grid"><span class="oh"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m oa"><x></x></span></div>
+<div class="grid"><span class="m os"><x></x></span></div>
+<div class="grid"><span class="m oh"><x></x></span></div>
+<div class="grid"><span class="m   "><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-004-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-004-ref.html
new file mode 100644
index 000000000..71ed28d7c
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-004-ref.html
@@ -0,0 +1,88 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: stretching items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 90px;
+  height: 50px;
+  grid: 7px 30px 3px / 7px 102px 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+.c2 { grid: 7px 30x 3px / 7px 112px 3px; grid-gap: 5px;}
+.c3 { grid: 7px 30x 3px / 7px 70px 3px; grid-gap: 5px;}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  min-width: 0;
+  max-width: 100px;
+}
+.h .grid > * {
+  min-height: 0;
+  max-height: 100px;
+  justify-self:center safe;
+  align-self:center safe;
+}
+.h > .grid { grid: 7px 102px 3px / 7px 70px 3px; grid-gap: 5px;}
+.h > .grid.c2 { grid: 7px 30px 3px / 7px 70px 3px; grid-gap: 5px;}
+.h > .grid.c3 { grid: 7px 108px 3px / 7px 70px 3px; grid-gap: 5px;}
+
+.oa { overflow: auto; }
+.p { width: 100%; }
+.h .grid > .p { height: 100%; }
+.x { width:5px; }
+.h .grid > .x { max-height:5px; }
+.m { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="p oa"><x></x></span></div>
+<div class="grid"><span class="p "><x></x></span></div>
+<div class="grid c2"><span class="p x" style="height:5px; margin-left:31.5px; margin-top:11.5px"><x></x></span></div>
+<div class="grid c2"><span class="  " style="width:68px"><x></x></span></div>
+
+<br>
+
+<div class="grid c3"><span class="p m oa"><x></x></span></div>
+<div class="grid c3"><span class="p m"><x></x></span></div>
+<div class="grid c2"><span class="m p x"><x></x></span></div>
+<div class="grid c2"><span class="m " style="width:58px"><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="p oa"><x></x></span></div>
+<div class="grid"><span class="p "><x></x></span></div>
+<div class="grid c2"><span class="p x" style=""><x></x></span></div>
+<div class="grid c2"><span class="  " style="height:28px; width:68px;"><x></x></span></div>
+
+<br>
+
+<div class="grid c3"><span class="m p oa"><x></x></span></div>
+<div class="grid c3"><span class="m p"><x></x></span></div>
+<div class="grid c2"><span class="m p x" style="justify-self:start;align-self:start"><x></x></span></div>
+<div class="grid c2"><span class="m  " style="height:22px; width:58px"><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-004.html b/layout/reftests/css-grid/grid-item-overflow-stretch-004.html
new file mode 100644
index 000000000..b983b5184
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-004.html
@@ -0,0 +1,82 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: stretching items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-004-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 90px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+  min-width: 0;
+  max-width: 100px;
+}
+.h .grid > * {
+  min-height: 0;
+  max-height: 100px;
+}
+
+.oa { overflow: auto; }
+.p { width: 100%; }
+.h .grid > .p { height: 100%; }
+.x { max-width:5px; margin:auto; }
+.h .grid > .x { max-height:5px; }
+.m { margin: 1px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class="p oa"><x></x></span></div>
+<div class="grid"><span class="p "><x></x></span></div>
+<div class="grid"><span class="p x"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="p m oa"><x></x></span></div>
+<div class="grid"><span class="p m"><x></x></span></div>
+<div class="grid"><span class="m p x"><x></x></span></div>
+<div class="grid"><span class="m "><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="p oa"><x></x></span></div>
+<div class="grid"><span class="p "><x></x></span></div>
+<div class="grid"><span class="p x"><x></x></span></div>
+<div class="grid"><span class="  "><x></x></span></div>
+
+<br>
+
+<div class="grid"><span class="m p oa"><x></x></span></div>
+<div class="grid"><span class="m p"><x></x></span></div>
+<div class="grid"><span class="m p x"><x></x></span></div>
+<div class="grid"><span class="m  "><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-005-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-005-ref.html
new file mode 100644
index 000000000..e7d353c8b
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-005-ref.html
@@ -0,0 +1,83 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: stretching overflow!=visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  min-width:0;
+  min-height:0;
+  box-sizing: border-box;
+}
+
+.oa, .os, .oh { width:80px; height:30px; }
+.m.oa, .m.os, .m.oh { width:70px; height:8px; }
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.ov { justify-self: start; }
+.m.ov { align-self: start; }
+.m  { margin: 17px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><input class="oa"></div>
+<div class="grid"><input class="os"></div>
+<div class="grid"><input class="oh"></div>
+<div class="grid"><input class="ov"></div>
+
+<br>
+
+<div class="grid"><input class="m oa"></div>
+<div class="grid"><input class="m os"></div>
+<div class="grid"><input class="m oh"></div>
+<div class="grid"><input class="m ov"></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><input class="oa"></div>
+<div class="grid"><input class="os"></div>
+<div class="grid"><input class="oh"></div>
+<div class="grid"><input class="ov"></div>
+
+<br>
+
+<div class="grid"><input class="m oa"></div>
+<div class="grid"><input class="m os"></div>
+<div class="grid"><input class="m oh"></div>
+<div class="grid"><input class="m ov"></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-005.html b/layout/reftests/css-grid/grid-item-overflow-stretch-005.html
new file mode 100644
index 000000000..33fe468d7
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-005.html
@@ -0,0 +1,77 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: stretching overflow!=visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-005-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px auto 3px / 7px auto 3px;
+  grid-gap: 5px;
+  border:1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border:1px solid;
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+}
+
+.oa { overflow: auto; }
+.os { overflow: scroll; }
+.oh { overflow: hidden; }
+.m  { margin: 17px 3px 5px 7px; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><input class="oa"></div>
+<div class="grid"><input class="os"></div>
+<div class="grid"><input class="oh"></div>
+<div class="grid"><input class="  "></div>
+
+<br>
+
+<div class="grid"><input class="m oa"></div>
+<div class="grid"><input class="m os"></div>
+<div class="grid"><input class="m oh"></div>
+<div class="grid"><input class="m   "></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><input class="oa"></div>
+<div class="grid"><input class="os"></div>
+<div class="grid"><input class="oh"></div>
+<div class="grid"><input class="  "></div>
+
+<br>
+
+<div class="grid"><input class="m oa"></div>
+<div class="grid"><input class="m os"></div>
+<div class="grid"><input class="m oh"></div>
+<div class="grid"><input class="m   "></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-006-ref.html b/layout/reftests/css-grid/grid-item-overflow-stretch-006-ref.html
new file mode 100644
index 000000000..71d4d4f54
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-006-ref.html
@@ -0,0 +1,54 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Reference: stretching overflow visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-flex;
+  width: 90px;
+  height: 40px;
+  padding: 7px 3px 3px 7px;
+  border: 1px solid;
+}
+
+.grid > * {
+  border: 1px solid;
+  margin: 5px;
+}
+
+.m  { margin: 6px 8px 10px 12px; }
+.ma { margin: auto; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class=""><x></x></span></div>
+<div class="grid"><span class="m"><x></x></span></div>
+<div class="grid"><span class="ma" style="margin-left:5px"><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class="" style="flex:1"><x></x></span></div>
+<div class="grid"><span class="m" style="flex:1"><x></x></span></div>
+<div class="grid"><span class="ma" style="margin-top:5px"><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-item-overflow-stretch-006.html b/layout/reftests/css-grid/grid-item-overflow-stretch-006.html
new file mode 100644
index 000000000..015c50fcc
--- /dev/null
+++ b/layout/reftests/css-grid/grid-item-overflow-stretch-006.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>CSS Grid Test: stretching overflow visible items</title>
+  <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1348857">
+  <link rel="match" href="grid-item-overflow-stretch-006-ref.html">
+  <style type="text/css">
+body,html { color:black; background:white; font:16px/1 monospace; padding:0; margin:0; }
+
+.grid {
+  display: inline-grid;
+  width: 100px;
+  height: 50px;
+  grid: 7px minmax(20px, auto) 3px / 7px minmax(20px, auto) 3px;
+  grid-gap: 5px;
+  border: 1px solid;
+}
+
+.grid > * {
+  grid-area: 2/2;
+  border: 1px solid;
+}
+
+.m  { margin: 1px 3px 5px 7px; }
+.ma { margin: auto; }
+
+x { display:block; width:110px; height:5px; background:grey; }
+.h .grid x { width:5px; height:110px; }
+
+br { clear:both; }
+  </style>
+</head>
+<body>
+
+<div class="grid"><span class=""><x></x></span></div>
+<div class="grid"><span class="m"><x></x></span></div>
+<div class="grid"><span class="ma"><x></x></span></div>
+
+<br>
+
+<div class="h">
+
+<div class="grid"><span class=""><x></x></span></div>
+<div class="grid"><span class="m"><x></x></span></div>
+<div class="grid"><span class="ma"><x></x></span></div>
+
+<br>
+
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/css-grid/grid-min-content-min-sizing-transferred-size-004-ref.html b/layout/reftests/css-grid/grid-min-content-min-sizing-transferred-size-004-ref.html
index 5fa60b3b5..04d047b83 100644
--- a/layout/reftests/css-grid/grid-min-content-min-sizing-transferred-size-004-ref.html
+++ b/layout/reftests/css-grid/grid-min-content-min-sizing-transferred-size-004-ref.html
@@ -36,7 +36,7 @@ var rowtest = [
 "min-width:80%; max-height:20px", "min-width:50%", "margin-left: 50px; width:50%"
 ];
 var results = [
-"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "24px/2px", "20px/2px", "20px/2px", "24px/2px", "24px/52px"
+"0/2px", "0/2px", "0/4px", "0/2px", "0/2px", "0/2px", "12px/2px", "20px/2px", "20px/2px", "24px/2px", "312px/52px"
 ];
 var item_height = [
 "0", "0", "0", "0", "0", "0", "12px", "20px", "20px", "24px", "312px"
diff --git a/layout/reftests/css-grid/reftest.list b/layout/reftests/css-grid/reftest.list
index d85eefbd0..093e2faee 100644
--- a/layout/reftests/css-grid/reftest.list
+++ b/layout/reftests/css-grid/reftest.list
@@ -116,6 +116,12 @@ skip-if(Android) == grid-auto-min-sizing-percent-001.html grid-auto-min-sizing-p
 == grid-item-auto-min-size-clamp-005.html grid-item-auto-min-size-clamp-005-ref.html
 == grid-item-auto-min-size-clamp-006.html grid-item-auto-min-size-clamp-006-ref.html
 == grid-item-auto-min-size-clamp-007.html grid-item-auto-min-size-clamp-007-ref.html
+== grid-item-overflow-stretch-001.html grid-item-overflow-stretch-001-ref.html
+== grid-item-overflow-stretch-002.html grid-item-overflow-stretch-002-ref.html
+== grid-item-overflow-stretch-003.html grid-item-overflow-stretch-003-ref.html
+== grid-item-overflow-stretch-004.html grid-item-overflow-stretch-004-ref.html
+== grid-item-overflow-stretch-005.html grid-item-overflow-stretch-005-ref.html
+== grid-item-overflow-stretch-006.html grid-item-overflow-stretch-006-ref.html
 == grid-item-canvas-001.html grid-item-canvas-001-ref.html
 skip-if(Android) == grid-item-button-001.html grid-item-button-001-ref.html
 == grid-item-table-stretch-001.html grid-item-table-stretch-001-ref.html
diff --git a/layout/reftests/forms/display-block-baselines-1-ref.html b/layout/reftests/forms/display-block-baselines-1-ref.html
new file mode 100644
index 000000000..d01c086b5
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-1-ref.html
@@ -0,0 +1,91 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Reference: Testcase #1 for bug 1330962</title>
+  <style type="text/css">
+@font-face {
+ src: url(../fonts/Ahem.ttf);
+ font-family: Ahem;
+}
+html,body {
+  color:black; background-color:white; font:16px/1 Ahem; padding:0; margin:0;
+}
+* { font:16px/1 Ahem; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-grid">
+    A<img class="block" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAEElEQVQoz2NgGAWjYBTAAAADEAABaJFtwwAAAABJRU5ErkJggg%3D%3D">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <input type="image" class="block" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAEElEQVQoz2NgGAWjYBTAAAADEAABaJFtwwAAAABJRU5ErkJggg%3D%3D">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><input type="text" value="text"></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><input type="text" value="text"></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><input type="text"></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><input class="no-theme" type="text" value="text"></div>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-1.html b/layout/reftests/forms/display-block-baselines-1.html
new file mode 100644
index 000000000..96ebdad71
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-1.html
@@ -0,0 +1,92 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Testcase #1 for bug 1330962</title>
+  <style type="text/css">
+@font-face {
+ src: url(../fonts/Ahem.ttf);
+ font-family: Ahem;
+}
+html,body {
+  color:black; background-color:white; font:16px/1 Ahem; padding:0; margin:0;
+}
+* { font:16px/1 Ahem; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <img class="block" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAEElEQVQoz2NgGAWjYBTAAAADEAABaJFtwwAAAABJRU5ErkJggg%3D%3D">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input type="image" class="block" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAEElEQVQoz2NgGAWjYBTAAAADEAABaJFtwwAAAABJRU5ErkJggg%3D%3D">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block" type="text" value="text">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block scroll" type="text" value="text">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block" type="text">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block no-theme" type="text" value="text">
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-2-ref.html b/layout/reftests/forms/display-block-baselines-2-ref.html
new file mode 100644
index 000000000..441a927b4
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-2-ref.html
@@ -0,0 +1,100 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Reference: Testcase #2 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+  color: black;
+  text-align: start;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A<div>
+    <div style="display:inline-block"><input type="button" value="button"></div></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><button>button</button></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><input class="no-theme" type="button" value="button"></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <button class="no-theme">button-first<div style="font-size:10px">button-last</div></button>
+  </div>
+  B
+  <div class="no-theme" style="display:inline-block">button-first<div style="font-size:10px">button-last</div></div>
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <button class="no-theme" style="display:inline-grid">button-first<x style="font-size:10px">button-last</x></button>
+  </div>
+  B
+  <div class="no-theme" style="display:inline-grid">button-first<x style="font-size:10px">button-last</x></div>
+</div>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <input type="checkbox" class="block" checked>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <input type="radio" class="block" checked>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-2.html b/layout/reftests/forms/display-block-baselines-2.html
new file mode 100644
index 000000000..78253fe4c
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-2.html
@@ -0,0 +1,100 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Testcase #2 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+  color: black;
+  text-align: start;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block" type="button" value="button">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <button class="block">button</button>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input class="block no-theme" type="button" value="button">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <button class="block no-theme">button-first<div style="font-size:10px">button-last</div></button>
+  </div>
+  B
+  <button class="no-theme">button-first<div style="font-size:10px">button-last</div></button>
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <button class="grid no-theme">button-first<x style="font-size:10px">button-last</x></button>
+  </div>
+  B
+  <button class="no-theme" style="display:inline-grid">button-first<x style="font-size:10px">button-last</x></button>
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input type="checkbox" class="block" checked>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input type="radio" class="block" checked>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-3-ref.html b/layout/reftests/forms/display-block-baselines-3-ref.html
new file mode 100644
index 000000000..ce277b50c
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-3-ref.html
@@ -0,0 +1,72 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Reference: Testcase #3 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <textarea class="block">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <textarea class="block no-theme">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-grid">
+    A
+    <textarea class="block no-theme no-scroll">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><fieldset style="display:inline">fieldset-first<br>fieldset-last</fieldset></div>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-3.html b/layout/reftests/forms/display-block-baselines-3.html
new file mode 100644
index 000000000..9f3c2b110
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-3.html
@@ -0,0 +1,73 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Testcase #3 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <textarea class="block">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <textarea class="block no-theme">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <textarea class="block no-theme no-scroll">textarea</textarea>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <fieldset class="block">fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-4-ref.html b/layout/reftests/forms/display-block-baselines-4-ref.html
new file mode 100644
index 000000000..5015d50c4
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-4-ref.html
@@ -0,0 +1,73 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Reference: Testcase #4 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <div style="display:inline-block"><fieldset style="display:inline"><legend>legend</legend>
+fieldset-first<br>fieldset-last</fieldset></div>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <fieldset style="display:inline-grid">grid-fieldset-first<x>grid-fieldset-last</x></fieldset>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <fieldset style="display:inline" class="no-theme">fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <fieldset style="display:inline" class="no-theme scroll">fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-4.html b/layout/reftests/forms/display-block-baselines-4.html
new file mode 100644
index 000000000..1bfd344b0
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-4.html
@@ -0,0 +1,74 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Testcase #4 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <fieldset class="block"><legend>legend</legend>
+fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <fieldset class="grid"><x style="order:2">grid-fieldset-last</x>grid-fieldset-first</fieldset>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <fieldset class="block no-theme">fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <fieldset class="block no-theme scroll">fieldset-first<br>fieldset-last</fieldset>
+  </div>
+  B
+</div>
+
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-5-ref.html b/layout/reftests/forms/display-block-baselines-5-ref.html
new file mode 100644
index 000000000..0dce47f59
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-5-ref.html
@@ -0,0 +1,72 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Reference: Testcase #5 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <input type="color">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <input type="color" class="no-theme">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <select><option>select</select>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A<br>
+    <select class="no-theme"><option>select</select>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/display-block-baselines-5.html b/layout/reftests/forms/display-block-baselines-5.html
new file mode 100644
index 000000000..0359c8a6f
--- /dev/null
+++ b/layout/reftests/forms/display-block-baselines-5.html
@@ -0,0 +1,72 @@
+<!DOCTYPE HTML>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html><head>
+  <meta charset="utf-8">
+  <title>Testcase #5 for bug 1330962</title>
+  <style type="text/css">
+html,body {
+  color:black; background-color:white; font:16px/1 monospace; padding:0; margin:0;
+}
+* { font:16px/1 monospace; }
+
+.block { display: block; }
+.grid { display: grid; }
+
+.no-theme {
+     -moz-appearance: none;
+  -webkit-appearance: none;
+          appearance: none;
+  padding: 20px 0;
+  border: none;
+  background: white;
+}
+
+.scroll {
+  overflow-y: scroll;
+}
+
+.no-scroll {
+  overflow: visible;
+}
+
+  </style>
+</head>
+<body>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input type="color" class="block">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <input type="color" class="block no-theme">
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <select class="block"><option>select</select>
+  </div>
+  B
+</div>
+
+<div>
+  <div style="display:inline-block">
+    A
+    <select class="block no-theme"><option>select</select>
+  </div>
+  B
+</div>
+
+</body>
+</html>
diff --git a/layout/reftests/forms/reftest.list b/layout/reftests/forms/reftest.list
index d45db276f..c7532077b 100644
--- a/layout/reftests/forms/reftest.list
+++ b/layout/reftests/forms/reftest.list
@@ -1,4 +1,9 @@
 fuzzy-if(skiaContent,1,10) HTTP(..) == text-control-baseline-1.html text-control-baseline-1-ref.html
+fuzzy-if(cocoaWidget,16,64) fuzzy-if(Android,52,64) fuzzy-if(/^Windows\x20NT\x206\.1/.test(http.oscpu),104,224) fuzzy-if(/^Windows\x20NT\x206\.2/.test(http.oscpu),57,400) == display-block-baselines-1.html display-block-baselines-1-ref.html # anti-aliasing issues
+== display-block-baselines-2.html display-block-baselines-2-ref.html
+== display-block-baselines-3.html display-block-baselines-3-ref.html
+== display-block-baselines-4.html display-block-baselines-4-ref.html
+fuzzy-if(Android,4,8) == display-block-baselines-5.html display-block-baselines-5-ref.html
 
 # button element
 include button/reftest.list
diff --git a/layout/reftests/svg/radialGradient-fr-01.svg b/layout/reftests/svg/radialGradient-fr-01.svg
new file mode 100644
index 000000000..2f28d3aba
--- /dev/null
+++ b/layout/reftests/svg/radialGradient-fr-01.svg
@@ -0,0 +1,27 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg"
+     xmlns:xlink="http://www.w3.org/1999/xlink">
+  <title>Test gradient fr attribute</title>
+  <defs>
+    <radialGradient id="grad1" fr="100%">
+      <stop offset="0%" stop-color="red" />
+      <stop offset="100%" stop-color="lime" />
+    </radialGradient>
+    <radialGradient id="grad2" xlink:href="#grad1"/>
+    <style>
+      circle {
+        stroke-width: 3px;
+        stroke: lime;
+      }
+    </style>
+  </defs>
+  <rect width="100%" height="100%" fill="lime"/>
+
+  <circle cx="100" cy="100" r="50" fill="url(#grad1)" />
+
+  <circle cx="300" cy="100" r="50" fill="url(#grad2)" />
+</svg>
+
diff --git a/layout/reftests/svg/radialGradient-fr-02-ref.svg b/layout/reftests/svg/radialGradient-fr-02-ref.svg
new file mode 100644
index 000000000..c256f72a2
--- /dev/null
+++ b/layout/reftests/svg/radialGradient-fr-02-ref.svg
@@ -0,0 +1,28 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg"
+     xmlns:xlink="http://www.w3.org/1999/xlink">
+  <title>Test gradient fr attribute</title>
+  <defs>
+    <radialGradient id="grad1">
+      <stop offset="0%" stop-color="red" />
+      <stop offset="20%" stop-color="red" />
+      <stop offset="100%" stop-color="lime" />
+    </radialGradient>
+    <style>
+      .cover {
+        stroke-width: 3px;
+        stroke: lime;
+        fill: none;
+        image-rendering: optimizeSpeed;
+      }
+    </style>
+  </defs>
+  <rect width="100%" height="100%" fill="lime"/>
+
+  <circle cx="100" cy="100" r="50" fill="url(#grad1)" />
+  <circle class="cover" cx="100" cy="100" r="50" fill="none"/>
+</svg>
+
diff --git a/layout/reftests/svg/radialGradient-fr-02.svg b/layout/reftests/svg/radialGradient-fr-02.svg
new file mode 100644
index 000000000..1933203be
--- /dev/null
+++ b/layout/reftests/svg/radialGradient-fr-02.svg
@@ -0,0 +1,27 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg"
+     xmlns:xlink="http://www.w3.org/1999/xlink">
+  <title>Test gradient fr attribute</title>
+  <defs>
+    <radialGradient id="grad1" fr="10%">
+      <stop offset="0%" stop-color="red" />
+      <stop offset="100%" stop-color="lime" />
+    </radialGradient>
+    <style>
+      .cover {
+        stroke-width: 3px;
+        stroke: lime;
+        fill: none;
+        image-rendering: optimizeSpeed;
+      }
+    </style>
+  </defs>
+  <rect width="100%" height="100%" fill="lime"/>
+
+  <circle cx="100" cy="100" r="50" fill="url(#grad1)" />
+  <circle class="cover" cx="100" cy="100" r="50" />
+</svg>
+
diff --git a/layout/reftests/svg/reftest.list b/layout/reftests/svg/reftest.list
index e596feae8..520adc9e6 100644
--- a/layout/reftests/svg/reftest.list
+++ b/layout/reftests/svg/reftest.list
@@ -290,6 +290,8 @@ fuzzy-if(skiaContent,3,5) == pattern-scale-01c.svg pattern-scale-01-ref.svg
 == radialGradient-basic-02.svg pass.svg
 fuzzy-if(cocoaWidget,4,15982) fuzzy-if(winWidget,4,92) fuzzy-if(skiaContent,4,60) == radialGradient-basic-03.svg radialGradient-basic-03-ref.svg
 == radialGradient-basic-04.svg pass.svg
+== radialGradient-fr-01.svg pass.svg
+fuzzy(1,3235) fuzzy-if(winWidget,1,6704) == radialGradient-fr-02.svg radialGradient-fr-02-ref.svg
 fuzzy-if(skiaContent,1,3600) == rect-01.svg pass.svg
 == rect-02.svg pass.svg
 == rect-03.svg pass.svg
diff --git a/layout/style/nsCSSParser.cpp b/layout/style/nsCSSParser.cpp
index 1108ce5b5..b361cf0c2 100644
--- a/layout/style/nsCSSParser.cpp
+++ b/layout/style/nsCSSParser.cpp
@@ -8918,6 +8918,10 @@ CSSParserImpl::ParseGridTrackSize(nsCSSValue& aValue,
     return CSSParseResult::NotFound;
   }
   if (mToken.mIdent.LowerCaseEqualsLiteral("fit-content")) {
+    if (requireFixedSize) {
+      UngetToken();
+      return CSSParseResult::Error;
+    }
     nsCSSValue::Array* func = aValue.InitFunction(eCSSKeyword_fit_content, 1);
     if (ParseGridTrackBreadth(func->Item(1)) == CSSParseResult::Ok &&
         func->Item(1).IsLengthPercentCalcUnit() &&
@@ -10400,7 +10404,8 @@ CSSParserImpl::ParseLinearGradient(nsCSSValue& aValue,
     UngetToken();
 
     // <angle> ,
-    if (ParseSingleTokenVariant(cssGradient->mAngle, VARIANT_ANGLE, nullptr) &&
+    if (ParseSingleTokenVariant(cssGradient->mAngle,
+                                VARIANT_ANGLE_OR_ZERO, nullptr) &&
         !ExpectSymbol(',', true)) {
       SkipUntil(')');
       return false;
diff --git a/layout/style/test/property_database.js b/layout/style/test/property_database.js
index 9c69e7d10..62d413d98 100644
--- a/layout/style/test/property_database.js
+++ b/layout/style/test/property_database.js
@@ -132,6 +132,9 @@ var validGradientAndElementValues = [
   "linear-gradient(to right bottom, red, 50%, green 50%, 50%, blue)",
   "linear-gradient(to right bottom, red, 0%, green 50%, 100%, blue)",
 
+  /* Unitless 0 is valid as an <angle> */
+  "linear-gradient(0, red, blue)",
+
   "-moz-linear-gradient(red, blue)",
   "-moz-linear-gradient(red, yellow, blue)",
   "-moz-linear-gradient(red 1px, yellow 20%, blue 24em, green)",
@@ -388,10 +391,8 @@ var invalidGradientAndElementValues = [
   "-moz-linear-gradient(10 10px -45deg, red, blue) repeat",
   "-moz-linear-gradient(10px 10 -45deg, red, blue) repeat",
   "linear-gradient(red -99, yellow, green, blue 120%)",
-  /* Unitless 0 is invalid as an <angle> */
-  "-moz-linear-gradient(top left 0, red, blue)",
-  "-moz-linear-gradient(5px 5px 0, red, blue)",
-  "linear-gradient(0, red, blue)",
+  /* Unitless nonzero numbers are valid as an <angle> */
+  "linear-gradient(30, red, blue)",
   /* Invalid color, calc() or -moz-image-rect() function */
   "linear-gradient(red, rgb(0, rubbish, 0) 50%, red)",
   "linear-gradient(red, red calc(50% + rubbish), red)",
@@ -6270,6 +6271,7 @@ if (IsCSSPropertyPrefEnabled("layout.css.grid.enabled")) {
       "repeat(auto-fill,minmax(1%,auto))",
       "repeat(auto-fill,minmax(1em,min-content)) minmax(min-content,0)",
       "repeat(auto-fill,minmax(max-content,1mm))",
+      "repeat(2, fit-content(1px))",
       "fit-content(1px) 1fr",
       "[a] fit-content(calc(1px - 99%)) [b]",
       "[a] fit-content(10%) [b c] fit-content(1em)",
@@ -6314,6 +6316,8 @@ if (IsCSSPropertyPrefEnabled("layout.css.grid.enabled")) {
       "repeat(1, repeat(1, 20px))",
       "repeat(auto-fill, auto)",
       "repeat(auto-fit,auto)",
+      "repeat(auto-fill, fit-content(1px))",
+      "repeat(auto-fit, fit-content(1px))",
       "repeat(auto-fit,[])",
       "repeat(auto-fill, 0) repeat(auto-fit, 0) ",
       "repeat(auto-fit, 0) repeat(auto-fill, 0) ",
@@ -6335,6 +6339,8 @@ if (IsCSSPropertyPrefEnabled("layout.css.grid.enabled")) {
       "fit-content(-1px)",
       "fit-content(auto)",
       "fit-content(min-content)",
+      "fit-content(1px) repeat(auto-fit, 1px)",
+      "fit-content(1px) repeat(auto-fill, 1px)",
     ],
     unbalanced_values: [
       "(foo] 40px",
diff --git a/layout/svg/nsSVGGradientFrame.cpp b/layout/svg/nsSVGGradientFrame.cpp
index 217ab8c4a..2d7684f5a 100644
--- a/layout/svg/nsSVGGradientFrame.cpp
+++ b/layout/svg/nsSVGGradientFrame.cpp
@@ -623,7 +623,7 @@ nsSVGRadialGradientFrame::GradientVectorLengthIsZero()
 already_AddRefed<gfxPattern>
 nsSVGRadialGradientFrame::CreateGradient()
 {
-  float cx, cy, r, fx, fy;
+  float cx, cy, r, fx, fy, fr;
 
   cx = GetLengthValue(dom::SVGRadialGradientElement::ATTR_CX);
   cy = GetLengthValue(dom::SVGRadialGradientElement::ATTR_CY);
@@ -631,6 +631,7 @@ nsSVGRadialGradientFrame::CreateGradient()
   // If fx or fy are not set, use cx/cy instead
   fx = GetLengthValue(dom::SVGRadialGradientElement::ATTR_FX, cx);
   fy = GetLengthValue(dom::SVGRadialGradientElement::ATTR_FY, cy);
+  fr = GetLengthValue(dom::SVGRadialGradientElement::ATTR_FR);
 
   if (fx != cx || fy != cy) {
     // The focal point (fFx and fFy) must be clamped to be *inside* - not on -
@@ -651,7 +652,7 @@ nsSVGRadialGradientFrame::CreateGradient()
     }
   }
 
-  RefPtr<gfxPattern> pattern = new gfxPattern(fx, fy, 0, cx, cy, r);
+  RefPtr<gfxPattern> pattern = new gfxPattern(fx, fy, fr, cx, cy, r);
   return pattern.forget();
 }