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ui/compositor/compositor.h

Index: ui/compositor/compositor.h
diff --git a/ui/compositor/compositor.h b/ui/compositor/compositor.h
index 5f4ed2ee4d2c564eef8fb6c1a79d2a75fa188cc3..1bce202ed9ae815c0f49a7753fba9c85c4b5d61c 100644
--- a/ui/compositor/compositor.h
+++ b/ui/compositor/compositor.h
@@ -141,6 +141,11 @@ class COMPOSITOR_EXPORT Compositor
   // Schedules a redraw of the layer tree associated with this compositor.
   void ScheduleDraw();
 
+  // When set, this blocks all drawing operations. This can be used to keep
+  // what's currently in the buffer and stop drawing anything new for any period
+  // of time. Unblocking will schedule a redraw so that the buffer can catch up.
+  void SetBlockDrawing(bool block_drawing);
+
   // Sets the root of the layer tree drawn by this Compositor. The root layer
   // must have no parent. The compositor's root layer is reset if the root layer
   // is destroyed. NULL can be passed to reset the root layer, in which case the
@@ -306,6 +311,9 @@ class COMPOSITOR_EXPORT Compositor
   // Prevent more than one draw from being scheduled.
   bool defer_draw_scheduling_;
 
+  // Block all drawing
+  bool block_drawing_;
+
   // Used to prevent Draw()s while a composite is in progress.
   bool waiting_on_compositing_end_;
   bool draw_on_compositing_end_;