Merge 133717

Source/WebCore/rendering/RenderBlock.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 515 matching lines @@
 {
     RenderBlock* firstChildIgnoringAnonymousWrappers = 0;
     for (RenderObject* curr = this; curr; curr = curr->parent()) {
         if (!curr->isRenderBlock() || curr->isFloatingOrOutOfFlowPositioned() || curr->isTableCell() || curr->isRoot() || curr->isRenderView() || curr->hasOverflowClip()
             || curr->isInlineBlockOrInlineTable())
             return 0;
 
         // FIXME: Table manages its own table parts, most of which are RenderBoxes.
         // Multi-column code cannot handle splitting the flow in table. Disabling it
         // to prevent crashes.
-        if (curr->isTable())
+        // Similarly, RenderButton maintains an anonymous block child and overrides
+        // addChild() to prevent itself from having additional direct children. This
+        // causes problems for split flows.
+        if (curr->isTable() || curr->isRenderButton())
             return 0;
         
         RenderBlock* currBlock = toRenderBlock(curr);
         if (!currBlock->createsAnonymousWrapper())
             firstChildIgnoringAnonymousWrappers = currBlock;
 
         if (currBlock->style()->specifiesColumns() && (allowAnonymousColumnBlock || !currBlock->isAnonymousColumnsBlock()))
             return firstChildIgnoringAnonymousWrappers;
             
         if (currBlock->isAnonymousColumnSpanBlock())
@@ skipping 7158 matching lines @@
 }
 
 String ValueToString<RenderBlock::FloatingObject*>::string(const RenderBlock::FloatingObject* floatingObject)
 {
     return String::format("%p (%dx%d %dx%d)", floatingObject, floatingObject->frameRect().pixelSnappedX(), floatingObject->frameRect().pixelSnappedY(), floatingObject->frameRect().pixelSnappedMaxX(), floatingObject->frameRect().pixelSnappedMaxY());
 }
 
 #endif
 
 } // namespace WebCore