1 files changed, 6 insertions, 60 deletions

diff --git a/layout/tables/nsTableRowFrame.cpp b/layout/tables/nsTableRowFrame.cpp
index 1b6051ef2..ea2477b73 100644
--- a/layout/tables/nsTableRowFrame.cpp
+++ b/layout/tables/nsTableRowFrame.cpp
@@ -561,65 +561,12 @@ nsTableRowFrame::CalcBSize(const ReflowInput& aReflowInput)
   return GetInitialBSize();
 }
 
-/**
- * We need a custom display item for table row backgrounds. This is only used
- * when the table row is the root of a stacking context (e.g., has 'opacity').
- * Table row backgrounds can extend beyond the row frame bounds, when
- * the row contains row-spanning cells.
- */
-class nsDisplayTableRowBackground : public nsDisplayTableItem {
-public:
-  nsDisplayTableRowBackground(nsDisplayListBuilder* aBuilder,
-                              nsTableRowFrame*      aFrame) :
-    nsDisplayTableItem(aBuilder, aFrame) {
-    MOZ_COUNT_CTOR(nsDisplayTableRowBackground);
-  }
-#ifdef NS_BUILD_REFCNT_LOGGING
-  virtual ~nsDisplayTableRowBackground() {
-    MOZ_COUNT_DTOR(nsDisplayTableRowBackground);
-  }
-#endif
-
-  virtual void Paint(nsDisplayListBuilder* aBuilder,
-                     nsRenderingContext*   aCtx) override;
-  NS_DISPLAY_DECL_NAME("TableRowBackground", TYPE_TABLE_ROW_BACKGROUND)
-};
-
-void
-nsDisplayTableRowBackground::Paint(nsDisplayListBuilder* aBuilder,
-                                   nsRenderingContext*   aCtx)
-{
-  auto rowFrame = static_cast<nsTableRowFrame*>(mFrame);
-  TableBackgroundPainter painter(rowFrame->GetTableFrame(),
-                                 TableBackgroundPainter::eOrigin_TableRow,
-                                 mFrame->PresContext(), *aCtx,
-                                 mVisibleRect, ToReferenceFrame(),
-                                 aBuilder->GetBackgroundPaintFlags());
-
-  DrawResult result = painter.PaintRow(rowFrame);
-  nsDisplayTableItemGeometry::UpdateDrawResult(this, result);
-}
-
 void
 nsTableRowFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                   const nsRect&           aDirtyRect,
                                   const nsDisplayListSet& aLists)
 {
-  nsDisplayTableItem* item = nullptr;
-  if (IsVisibleInSelection(aBuilder)) {
-    bool isRoot = aBuilder->IsAtRootOfPseudoStackingContext();
-    if (isRoot) {
-      // This background is created regardless of whether this frame is
-      // visible or not. Visibility decisions are delegated to the
-      // table background painter.
-      // We would use nsDisplayGeneric for this rare case except that we
-      // need the background to be larger than the row frame in some
-      // cases.
-      item = new (aBuilder) nsDisplayTableRowBackground(aBuilder, this);
-      aLists.BorderBackground()->AppendNewToTop(item);
-    }
-  }
-  nsTableFrame::DisplayGenericTablePart(aBuilder, this, aDirtyRect, aLists, item);
+  nsTableFrame::DisplayGenericTablePart(aBuilder, this, aDirtyRect, aLists);
 }
 
 nsIFrame::LogicalSides
@@ -979,12 +926,11 @@ nsTableRowFrame::ReflowChildren(nsPresContext*           aPresContext,
         // be merged into the else below if we can.)
         nsMargin* computedOffsetProp =
           kidFrame->GetProperty(nsIFrame::ComputedOffsetProperty());
-        // Bug 975644: a position:sticky kid can end up with a null
-        // property value here.
-        LogicalMargin computedOffsets(wm, computedOffsetProp ?
-                                            *computedOffsetProp : nsMargin());
-        ReflowInput::ApplyRelativePositioning(kidFrame, wm, computedOffsets,
-                                                    &kidPosition, containerSize);
+
+        // On our fist reflow sticky children may not have the property yet (we
+        // need to reflow the children first to size the scroll frame).
+        LogicalMargin computedOffsets(wm, computedOffsetProp ? *computedOffsetProp : nsMargin());
+        ReflowInput::ApplyRelativePositioning(kidFrame, wm, computedOffsets, &kidPosition, containerSize);
       }
 
       // In vertical-rl mode, we are likely to have containerSize.width = 0