[REGRESSION] Button cannot be clicked with text-indent : -99999999px after r143483.

Source/core/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 1489 matching lines @@
         LayoutRect rectToApply;
         if (isHorizontalWritingMode())
             rectToApply = LayoutRect(clientRect.x(), clientRect.y(), 1, max<LayoutUnit>(0, oldClientAfterEdge - clientRect.y()));
         else
             rectToApply = LayoutRect(clientRect.x(), clientRect.y(), max<LayoutUnit>(0, oldClientAfterEdge - clientRect.x()), 1);
         addLayoutOverflow(rectToApply);
         if (hasRenderOverflow())
             m_overflow->setLayoutClientAfterEdge(oldClientAfterEdge);
     }
 
-    // Allow our overflow to catch cases where the caret in an empty editable element with negative text indent needs to get painted.
-    LayoutUnit textIndent = textIndentOffset();
-    if (textIndent < 0) {
-        LayoutRect clientRect(noOverflowRect());
-        LayoutRect rectToApply = LayoutRect(clientRect.x() + textIndent, clientRect.y(), clientRect.width() - textIndent, clientRect.height());
-        addContentsVisualOverflow(rectToApply);
-    }
-
     // Add visual overflow from box-shadow and border-image-outset.
     addVisualEffectOverflow();
 
     // Add visual overflow from theme.
     addVisualOverflowFromTheme();
 
     if (isRenderNamedFlowThread())
         toRenderNamedFlowThread(this)->computeOversetStateForRegions(oldClientAfterEdge);
 }
 
@@ skipping 4260 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore