Merge 138994

Source/WebCore/html/canvas/CanvasRenderingContext2D.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  * Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 2342 matching lines @@
     else if (state().m_lineCap == SquareCap)
         delta *= root2;
 
     rect.inflate(delta);
 }
 
 const Font& CanvasRenderingContext2D::accessFont()
 {
     canvas()->document()->updateStyleIfNeeded();
 
-    if (!state().m_realizedFont)
-        setFont(state().m_unparsedFont);
+    if (!state().m_realizedFont) {
+        // Create temporary string object to hold ref count in case
+        // state().m_unparsedFont in unreffed by call to realizeSaves in
+        // setFont.
+        String unparsedFont(state().m_unparsedFont);
+        setFont(unparsedFont);
+    }
     return state().m_font;
 }
 
 #if ENABLE(ACCELERATED_2D_CANVAS) && USE(ACCELERATED_COMPOSITING)
 PlatformLayer* CanvasRenderingContext2D::platformLayer() const
 {
     return canvas()->buffer() ? canvas()->buffer()->platformLayer() : 0;
 }
 #endif
 
 bool CanvasRenderingContext2D::webkitImageSmoothingEnabled() const
 {
     return state().m_imageSmoothingEnabled;
 }
 
 void CanvasRenderingContext2D::setWebkitImageSmoothingEnabled(bool enabled)
 {
     if (enabled == state().m_imageSmoothingEnabled)
         return;
 
     realizeSaves();
     modifiableState().m_imageSmoothingEnabled = enabled;
     drawingContext()->setImageInterpolationQuality(enabled ? DefaultInterpolationQuality : InterpolationNone);
 }
 
 } // namespace WebCore