Plumb cc::LatencyInfo through command buffer and output surface

cc/output_surface.h

Index: cc/output_surface.h
diff --git a/cc/output_surface.h b/cc/output_surface.h
index f128dc2d226a2ac18deb5651f96e9badb1d8f8ae..47cf76a0e575dd51922066384ae1f5265c5c9a52 100644
--- a/cc/output_surface.h
+++ b/cc/output_surface.h
@@ -23,6 +23,7 @@ namespace cc {
 
 class CompositorFrame;
 class OutputSurfaceClient;
+struct LatencyInfo;
 
 // Represents the output surface for a compositor. The compositor owns
 // and manages its destruction. Its lifetime is:
@@ -92,6 +93,8 @@ class CC_EXPORT OutputSurface : public WebKit::WebCompositorOutputSurface {
   // processing should be stopped, or lowered in priority.
   virtual void UpdateSmoothnessTakesPriority(bool prefer_smoothness) {}
 
+  virtual void SetLatencyInfo(const LatencyInfo&) {}

[piman, 2013/03/19 04:30:29]

What calls this, and in particular, what ensures ordering wrt the swap (i.e.
calls Flush)? What is the proper ordering?

Agreed with Nat, this should probably be folded into
SwapBuffers/PostSubBuffer/SendFrameToParentCompositor (and the 2 former maybe
folded into the latter).

+
  protected:
   OutputSurfaceClient* client_;
   struct cc::OutputSurface::Capabilities capabilities_;