GraphicsContext culling support.

Source/platform/graphics/GraphicsContext.cpp

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google 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
@@ skipping 1507 matching lines @@
 void GraphicsContext::clipRRect(const SkRRect& rect, AntiAliasingMode aa, SkRegion::Op op)
 {
     if (paintingDisabled())
         return;
 
     realizeCanvasSave(SkCanvas::kClip_SaveFlag);
 
     m_canvas->clipRRect(rect, op, aa == AntiAliased);
 }
 
+void GraphicsContext::beginCull(const FloatRect& rect)
+{
+    if (paintingDisabled())
+        return;
+
+    realizeCanvasSave(SkCanvas::kMatrixClip_SaveFlag);
+    m_canvas->pushCull(rect);
+}
+
+void GraphicsContext::endCull()
+{
+    if (paintingDisabled())
+        return;
+
+    realizeCanvasSave(SkCanvas::kMatrixClip_SaveFlag);
+
+    m_canvas->popCull();
+}
+
 void GraphicsContext::rotate(float angleInRadians)
 {
     if (paintingDisabled())
         return;
 
     realizeCanvasSave(SkCanvas::kMatrix_SaveFlag);
 
     m_canvas->rotate(WebCoreFloatToSkScalar(angleInRadians * (180.0f / 3.14159265f)));
 }
 
@@ skipping 347 matching lines @@
 
 void GraphicsContext::didDrawTextInRect(const SkRect& textRect)
 {
     if (m_trackTextRegion) {
         TRACE_EVENT0("skia", "PlatformContextSkia::trackTextRegion");
         m_textRegion.join(textRect);
     }
 }
 
 }