Canvas objects did not mark themselves for layout when they're a flex item

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

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 53 matching lines @@
 
     if (!parent())
         return;
 
     if (!preferredLogicalWidthsDirty())
         setPreferredLogicalWidthsDirty();
 
     LayoutSize oldSize = size();
     updateLogicalWidth();
     updateLogicalHeight();
-    if (oldSize == size())
+    if (oldSize == size() && !hasOverrideLogicalContentWidth() && !hasOverrideLogicalContentHeight()) {
+        // If we have an override size, then we're probably a flex item, and the
+        // check above is insufficient because updateLogical{Width,Height} just
+        // used the override size. We actually have to mark ourselves as needing
+        // layout so the flex algorithm can run and compute our size correctly.
         return;
+    }
 
     if (!selfNeedsLayout())
         setNeedsLayout(LayoutInvalidationReason::SizeChanged);
 }
 
 PaintInvalidationReason LayoutHTMLCanvas::invalidatePaintIfNeeded(const PaintInvalidationState& paintInvalidationState)
 {
     PaintInvalidationReason reason = LayoutBox::invalidatePaintIfNeeded(paintInvalidationState);
     HTMLCanvasElement* element = toHTMLCanvasElement(node());
     if (element->isDirty()) {
@@ skipping 11 matching lines @@
     return CompositingReasonNone;
 }
 
 void LayoutHTMLCanvas::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
 {
     LayoutReplaced::styleDidChange(diff, oldStyle);
     toHTMLCanvasElement(node())->styleDidChange(oldStyle, styleRef());
 }
 
 } // namespace blink