Mark/unmark orthogonal writing-mode roots when ancestors were changed

third_party/WebKit/Source/core/layout/LayoutBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 247 matching lines @@
     }
 
     return oldStyle.borderTopWidth() != newStyle.borderTopWidth()
         || oldStyle.borderBottomWidth() != newStyle.borderBottomWidth()
         || oldStyle.paddingTop() != newStyle.paddingTop()
         || oldStyle.paddingBottom() != newStyle.paddingBottom();
 }
 
 void LayoutBlock::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
 {
+    // Horizontal writing mode definition is updated in LayoutBoxModelObject::updateFromStyle,
+    // (as part of the LayoutBoxModelObject::styleDidChange call below). So, we can safely cache the horizontal
+    // writing mode value before style change here.
+    bool oldHorizontalWritingMode = isHorizontalWritingMode();
+
     LayoutBox::styleDidChange(diff, oldStyle);
 
     if (isFloatingOrOutOfFlowPositioned() && oldStyle && !oldStyle->isFloating() && !oldStyle->hasOutOfFlowPosition() && parent() && parent()->isLayoutBlockFlow()) {
         toLayoutBlock(parent())->makeChildrenInlineIfPossible();
         // Reparent to an adjacent anonymous block if one is available.
         if (previousSibling() && previousSibling()->isAnonymousBlock())
             toLayoutBlock(parent())->moveChildTo(toLayoutBlock(previousSibling()), this, nullptr, false);
         else if (nextSibling() && nextSibling()->isAnonymousBlock())
             toLayoutBlock(parent())->moveChildTo(toLayoutBlock(nextSibling()), this, nextSibling()->slowFirstChild(), false);
     }
 
     const ComputedStyle& newStyle = styleRef();
 
     if (oldStyle && parent()) {
         if (oldStyle->position() != newStyle.position() && newStyle.position() != StaticPosition) {
             // Remove our absolute and fixed positioned descendants from their new containing block,
             // in case containingBlock() changes by the change to the position property.
             // See styleWillChange() for other cases.
             if (LayoutBlock* cb = containingBlock())
                 cb->removePositionedObjects(this, NewContainingBlock);
         }
+
+        // Changing the writingMode() may change isOrthogonalWritingModeRoot()
+        // of children. Make sure all children are marked/unmarked as orthogonal
+        // writing-mode roots.
+        bool newHorizontalWritingMode = isHorizontalWritingMode();
+        if (oldHorizontalWritingMode != newHorizontalWritingMode) {
+            for (LayoutObject* child = firstChild(); child; child = child->nextSibling()) {
+                if (!child->isBox())
+                    continue;
+                if (newHorizontalWritingMode != child->isHorizontalWritingMode())
+                    toLayoutBox(child)->markOrthogonalWritingModeRoot();
+                else
+                    toLayoutBox(child)->unmarkOrthogonalWritingModeRoot();
+            }
+        }
     }
 
     if (TextAutosizer* textAutosizer = document().textAutosizer())
         textAutosizer->record(this);
 
     propagateStyleToAnonymousChildren(true);
 
     // It's possible for our border/padding to change, but for the overall logical width of the block to
     // end up being the same. We keep track of this change so in layoutBlock, we can know to set relayoutChildren=true.
     m_widthAvailableToChildrenChanged |= oldStyle && diff.needsFullLayout() && needsLayout() && borderOrPaddingLogicalWidthChanged(*oldStyle, newStyle);
@@ skipping 2566 matching lines @@
 void LayoutBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const LayoutObject* obj) const
 {
     showLayoutObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink