gpu: Remove Echo and SwapCompletion GL interfacess

cc/test/test_context_support.h

Index: cc/test/test_context_support.h
diff --git a/cc/test/test_context_support.h b/cc/test/test_context_support.h
index 1349053e920bad85ef3da1d6c781edbb4da46bf3..0ffc683c8aaf481d6aaf22ffbe25781e3b6e02e8 100644
--- a/cc/test/test_context_support.h
+++ b/cc/test/test_context_support.h
@@ -27,8 +27,6 @@ class TestContextSupport : public gpu::ContextSupport {
   virtual void PartialSwapBuffers(const gfx::Rect& sub_buffer) OVERRIDE;
   virtual uint32 InsertFutureSyncPointCHROMIUM() OVERRIDE;
   virtual void RetireSyncPointCHROMIUM(uint32 sync_point) OVERRIDE;
-  virtual void SetSwapBuffersCompleteCallback(
-      const base::Closure& callback) OVERRIDE;
   virtual void ScheduleOverlayPlane(int plane_z_order,
                                     gfx::OverlayTransform plane_transform,
                                     unsigned overlay_texture_id,
@@ -62,14 +60,10 @@ class TestContextSupport : public gpu::ContextSupport {
   }
 
  private:
-  void OnSwapBuffersComplete();
-
   std::vector<base::Closure> sync_point_callbacks_;
   SurfaceVisibleCallback set_visible_callback_;
   ScheduleOverlayPlaneCallback schedule_overlay_plane_callback_;
 
-  base::Closure swap_buffers_complete_callback_;
-
   SwapType last_swap_type_;
   gfx::Rect last_partial_swap_rect_;