Unified BeginFrame scheduling

cc/trees/layer_tree_host_client.h

Index: cc/trees/layer_tree_host_client.h
diff --git a/cc/trees/layer_tree_host_client.h b/cc/trees/layer_tree_host_client.h
index 74dcbc0cff24631873737c4cdc42341e1051f4ed..09752e90f7379e0b276e7cc70472d0193bcf4cb0 100644
--- a/cc/trees/layer_tree_host_client.h
+++ b/cc/trees/layer_tree_host_client.h
@@ -8,6 +8,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
+#include "cc/base/cc_export.h"
 
 namespace gfx {
 class Vector2d;
@@ -17,8 +18,9 @@ namespace cc {
 class ContextProvider;
 class InputHandlerClient;
 class OutputSurface;
+struct BeginFrameArgs;
 
-class LayerTreeHostClient {
+class CC_EXPORT LayerTreeHostClient {
  public:
   virtual void WillBeginMainFrame(int frame_id) = 0;
   // Marks finishing compositing-related tasks on the main thread. In threaded
@@ -32,11 +34,14 @@ class LayerTreeHostClient {
   // create an OutputSurface that is guaranteed to initialize correctly.
   virtual scoped_ptr<OutputSurface> CreateOutputSurface(bool fallback) = 0;
   virtual void DidInitializeOutputSurface() = 0;
+  virtual void DidLoseOutputSurface() = 0;
   virtual void WillCommit() = 0;
   virtual void DidCommit() = 0;
   virtual void DidCommitAndDrawFrame() = 0;
   virtual void DidCompleteSwapBuffers() = 0;
 
+  virtual void SendBeginFrameToChildren(const BeginFrameArgs& args);
+
   // Requests that the client insert a rate limiting token in the shared main
   // thread context's command stream that will block if the context gets too far
   // ahead of the compositor's command stream. Only needed if the tree contains