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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 887cb73f79b9fbfeccf6a460aa98eeaeaaab1987..16368ff58b4cdc0aaaa2251a4bc6e8636ff3b102 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.h
+++ b/content/browser/renderer_host/render_widget_host_view_mac.h
@@ -374,7 +374,8 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   // Update the IOSurface to be drawn and call setNeedsDisplay on
   // |cocoa_view_|.
   void CompositorSwapBuffers(IOSurfaceID surface_handle,
-                             const gfx::Size& size,
+                             const gfx::Rect& damage_rect,
+                             const gfx::Size& surface_size,
                              float scale_factor,
                              const std::vector<ui::LatencyInfo>& latency_info);
 
@@ -616,6 +617,11 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   // Display link for getting vsync info.
   scoped_refptr<DisplayLinkMac> display_link_;
 
+  // The current VSync timebase and interval. This is zero until the first call
+  // to SendVSyncParametersToRenderer(), and refreshed regularly thereafter.
+  base::TimeTicks vsync_timebase_;
+  base::TimeDelta vsync_interval_;
+
   // The current composition character range and its bounds.
   gfx::Range composition_range_;
   std::vector<gfx::Rect> composition_bounds_;