Move GraphicsLayerUpdater::rebuildTree into its own file

Source/core/rendering/compositing/GraphicsLayerTreeBuilder.h

Index: Source/core/rendering/compositing/GraphicsLayerTreeBuilder.h
diff --git a/public/platform/WebCompositeAndReadbackAsyncCallback.h b/Source/core/rendering/compositing/GraphicsLayerTreeBuilder.h
similarity index 73%
copy from public/platform/WebCompositeAndReadbackAsyncCallback.h
copy to Source/core/rendering/compositing/GraphicsLayerTreeBuilder.h
index 45a61be2332878a751a1f8d2b5cbe278f2be46da..4389ebe7f830847a86e778b00e3d48ecdb4aa05a 100644
--- a/public/platform/WebCompositeAndReadbackAsyncCallback.h
+++ b/Source/core/rendering/compositing/GraphicsLayerTreeBuilder.h
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -23,18 +24,24 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef WebCompositeAndReadbackAsyncCallback_h
-#define WebCompositeAndReadbackAsyncCallback_h
+#ifndef GraphicsLayerTreeBuilder_h
+#define GraphicsLayerTreeBuilder_h
 
-class SkBitmap;
+#include "platform/graphics/GraphicsLayer.h"
+#include "wtf/Vector.h"
 
-namespace blink {
+namespace WebCore {
 
-class WebCompositeAndReadbackAsyncCallback {
+class RenderLayer;
+
+class GraphicsLayerTreeBuilder {
 public:
-    virtual void didCompositeAndReadback(const SkBitmap&) = 0;
+    GraphicsLayerTreeBuilder();
+    ~GraphicsLayerTreeBuilder();
+
+    void rebuild(RenderLayer&, GraphicsLayerVector& childLayersOfEnclosingLayer);
 };
 
-} // namespace blink
+} // namespace WebCore
 
-#endif // WebCompositeAndReadbackAsyncCallback_h
+#endif // GraphicsLayerTreeBuilder_h