Remove SendBeginFramesToChildren plumbing

content/browser/renderer_host/render_widget_host_view_mac.h

Index: content/browser/renderer_host/render_widget_host_view_mac.h
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.h b/content/browser/renderer_host/render_widget_host_view_mac.h
index bde64e72a73e4e5782c3ddfeeb74e82035351ea9..67acd3d50b9a8e411e10b77f80f29a6a19acbdf2 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.h
+++ b/content/browser/renderer_host/render_widget_host_view_mac.h
@@ -22,6 +22,7 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "cc/scheduler/begin_frame_source.h"
 #include "cc/surfaces/surface_id.h"
 #include "content/browser/renderer_host/browser_compositor_view_mac.h"
 #include "content/browser/renderer_host/delegated_frame_host.h"
@@ -229,7 +230,8 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
       public DelegatedFrameHostClient,
       public ui::AcceleratedWidgetMacNSView,
       public IPC::Sender,
-      public gfx::DisplayObserver {
+      public gfx::DisplayObserver,
+      public cc::BeginFrameObserverBase {
  public:
   // The view will associate itself with the given widget. The native view must
   // be hooked up immediately to the view hierarchy, or else when it is
@@ -365,6 +367,9 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   // Forwards the mouse event to the renderer.
   void ForwardMouseEvent(const blink::WebMouseEvent& event);
 
+  // Called when RenderWidget wants to start BeginFrame scheduling or stop.
+  void OnSetNeedsBeginFrames(bool needs_begin_frames);
+
   void KillSelf();
 
   void SetTextInputActive(bool active);
@@ -505,6 +510,11 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   void DelegatedFrameHostUpdateVSyncParameters(
       const base::TimeTicks& timebase,
       const base::TimeDelta& interval) override;
+  void SetBeginFrameSource(cc::BeginFrameSource* source) override;
+
+  // cc::BeginFrameObserverBase implementation.
+  bool OnBeginFrameDerivedImpl(const cc::BeginFrameArgs& args) override;
+  void OnBeginFrameSourcePausedChanged(bool paused) override;
 
   // AcceleratedWidgetMacNSView implementation.
   NSView* AcceleratedWidgetGetNSView() const override;
@@ -592,6 +602,10 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   base::TimeTicks vsync_timebase_;
   base::TimeDelta vsync_interval_;
 
+  // The begin frame source being observed.  Null if none.
+  cc::BeginFrameSource* begin_frame_source_;
+  bool needs_begin_frames_;
+
   // The current composition character range and its bounds.
   gfx::Range composition_range_;
   std::vector<gfx::Rect> composition_bounds_;