cc: Route offscreen context creation for compositor to the browser.

cc/single_thread_proxy.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_SINGLE_THREAD_PROXY_H_
 #define CC_SINGLE_THREAD_PROXY_H_
 
 #include <limits>
 
 #include "base/time.h"
 #include "cc/animation_events.h"
 #include "cc/layer_tree_host_impl.h"
 #include "cc/proxy.h"
 
 namespace cc {
 
+class ContextProvider;
 class LayerTreeHost;
 
 class SingleThreadProxy : public Proxy, LayerTreeHostImplClient {
 public:
     static scoped_ptr<Proxy> create(LayerTreeHost*);
     virtual ~SingleThreadProxy();
 
     // Proxy implementation
     virtual bool compositeAndReadback(void *pixels, const gfx::Rect&) OVERRIDE;
     virtual void startPageScaleAnimation(gfx::Vector2d targetOffset, bool useAnchor, float scale, base::TimeDelta duration) OVERRIDE;
@@ skipping 39 matching lines @@
     virtual void renewTreePriority() OVERRIDE { }
 
     // Called by the legacy path where RenderWidget does the scheduling.
     void compositeImmediately();
 
 private:
     explicit SingleThreadProxy(LayerTreeHost*);
 
     bool commitAndComposite();
     void doCommit(scoped_ptr<ResourceUpdateQueue>);
-    bool doComposite();
+    bool doComposite(scoped_refptr<cc::ContextProvider> offscreenContextProvider);
     void didSwapFrame();
 
     // Accessed on main thread only.
     LayerTreeHost* m_layerTreeHost;
     bool m_outputSurfaceLost;
+    bool m_createdOffscreenContextProvider;
 
     // Holds on to the context between initializeContext() and initializeRenderer() calls. Shouldn't
     // be used for anything else.
     scoped_ptr<OutputSurface> m_outputSurfaceBeforeInitialization;
 
     // Used on the Thread, but checked on main thread during initialization/shutdown.
     scoped_ptr<LayerTreeHostImpl> m_layerTreeHostImpl;
     bool m_rendererInitialized;
     RendererCapabilities m_RendererCapabilitiesForMainThread;
 
@@ skipping 62 matching lines @@
     {
     }
 private:
     DebugScopedSetImplThread m_implThread;
     DebugScopedSetMainThreadBlocked m_mainThreadBlocked;
 };
 
 } // namespace cc
 
 #endif  // CC_SINGLE_THREAD_PROXY_H_