Move Insert/SignalSyncPoint() to GpuControl

gpu/command_buffer/common/gpu_control.h

Index: gpu/command_buffer/common/gpu_control.h
diff --git a/gpu/command_buffer/common/gpu_control.h b/gpu/command_buffer/common/gpu_control.h
index 61b5cb154e0f6bd645e2105b0a2316c752534910..84a63737bff113f6f5d83707422109a3a3528591 100644
--- a/gpu/command_buffer/common/gpu_control.h
+++ b/gpu/command_buffer/common/gpu_control.h
@@ -7,6 +7,7 @@
 
 #include <vector>
 
+#include "base/callback.h"
 #include "gpu/command_buffer/common/mailbox.h"
 #include "gpu/command_buffer/common/types.h"
 #include "gpu/gpu_export.h"
@@ -41,6 +42,14 @@ class GPU_EXPORT GpuControl {
   virtual bool GenerateMailboxNames(unsigned num,
                                     std::vector<gpu::Mailbox>* names) = 0;
 
+  // Inserts a sync point, returning its ID. Sync point IDs are global and can
+  // be used for cross-context synchronization.
+  virtual uint32 InsertSyncPoint() = 0;
+
+  // Runs |callback| when a sync point is reached.
+  virtual void SignalSyncPoint(uint32 sync_point,
+                               const base::Closure& callback) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GpuControl);
 };