Issue #1641 - Implement CSS flow-root keyword

This is just a clean port of 1322191 and follow-up 1325970. It really seems to add create a new way to access existing code relating to block formatting and floating elements rather than implementing new functionality, and it is mercifully straightforwards.

1 files changed, 5 insertions, 3 deletions

diff --git a/layout/base/nsCSSFrameConstructor.cpp b/layout/base/nsCSSFrameConstructor.cpp
index fc458b5eb..21068b673 100644
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -2618,7 +2618,8 @@ nsCSSFrameConstructor::ConstructDocElementFrame(Element*                 aDocEle
     newFrame = frameItems.FirstChild();
     NS_ASSERTION(frameItems.OnlyChild(), "multiple root element frames");
   } else {
-    MOZ_ASSERT(display->mDisplay == StyleDisplay::Block,
+    MOZ_ASSERT(display->mDisplay == StyleDisplay::Block ||
+               display->mDisplay == StyleDisplay::FlowRoot,
                "Unhandled display type for root element");
     contentFrame = NS_NewBlockFormattingContext(mPresShell, styleContext);
     nsFrameItems frameItems;
@@ -4741,6 +4742,7 @@ nsCSSFrameConstructor::FindDisplayData(const nsStyleDisplay* aDisplay,
   static const FrameConstructionDataByDisplay sDisplayData[] = {
     FCDATA_FOR_DISPLAY(StyleDisplay::None, UNREACHABLE_FCDATA()),
     FCDATA_FOR_DISPLAY(StyleDisplay::Block, UNREACHABLE_FCDATA()),
+    FCDATA_FOR_DISPLAY(StyleDisplay::FlowRoot, UNREACHABLE_FCDATA()),
     // To keep the hash table small don't add inline frames (they're
     // typically things like FONT and B), because we can quickly
     // find them if we need to.
@@ -4926,7 +4928,7 @@ nsCSSFrameConstructor::ConstructNonScrollableBlockWithConstructor(
        StyleDisplay::InlineBlock == aDisplay->mDisplay ||
        clipPaginatedOverflow) &&
       !aParentFrame->IsSVGText()) {
-    flags = NS_BLOCK_FLOAT_MGR | NS_BLOCK_MARGIN_ROOT;
+    flags = NS_BLOCK_FORMATTING_CONTEXT_STATE_BITS;
     if (clipPaginatedOverflow) {
       flags |= NS_BLOCK_CLIP_PAGINATED_OVERFLOW;
     }
@@ -5119,7 +5121,7 @@ nsCSSFrameConstructor::FlushAccumulatedBlock(nsFrameConstructorState& aState,
   // is not a suitable block.
   nsContainerFrame* blockFrame =
     NS_NewMathMLmathBlockFrame(mPresShell, blockContext);
-  blockFrame->AddStateBits(NS_BLOCK_FLOAT_MGR | NS_BLOCK_MARGIN_ROOT);
+  blockFrame->AddStateBits(NS_BLOCK_FORMATTING_CONTEXT_STATE_BITS);
 
   InitAndRestoreFrame(aState, aContent, aParentFrame, blockFrame);
   ReparentFrames(this, blockFrame, aBlockItems);