Remove clips where we can show that they are unnecessary.

Source/core/rendering/RenderBlockLineLayout.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
  * Copyright (C) 2010 Google Inc. 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
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 3299 matching lines @@
 }
 
 void RenderBlock::addOverflowFromInlineChildren()
 {
     LayoutUnit endPadding = hasOverflowClip() ? paddingEnd() : LayoutUnit();
     // FIXME: Need to find another way to do this, since scrollbars could show when we don't want them to.
     if (hasOverflowClip() && !endPadding && node() && node()->isRootEditableElement() && style()->isLeftToRightDirection())
         endPadding = 1;
     for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
         addLayoutOverflow(curr->paddedLayoutOverflowRect(endPadding));
-        if (!hasOverflowClip())
-            addVisualOverflow(curr->visualOverflowRect(curr->lineTop(), curr->lineBottom()));
+        LayoutRect visualOverflow = curr->visualOverflowRect(curr->lineTop(), curr->lineBottom());
+        addVisualOverflow(visualOverflow, VisualOverflowClippedByContentsClip);
     }
 }
 
 void RenderBlock::deleteEllipsisLineBoxes()
 {
     ETextAlign textAlign = style()->textAlign();
     bool ltr = style()->isLeftToRightDirection();
     bool firstLine = true;
     for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
         if (curr->hasEllipsisBox()) {
@@ skipping 150 matching lines @@
     lineGridBox->alignBoxesInBlockDirection(logicalHeight(), textBoxDataMap, verticalPositionCache);
 
     setLineGridBox(lineGridBox);
 
     // FIXME: If any of the characteristics of the box change compared to the old one, then we need to do a deep dirtying
     // (similar to what happens when the page height changes). Ideally, though, we only do this if someone is actually snapping
     // to this grid.
 }
 
 }