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ui/compositor/compositor.cc

Index: ui/compositor/compositor.cc
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index e68d6370415e8b1f9addb956b10d4728b8689ed5..8f11ee3b7ebe18f24c885cfe4fff089d7c223547 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -83,6 +83,7 @@ Compositor::Compositor(gfx::AcceleratedWidget widget,
       disable_schedule_composite_(false),
       compositor_lock_(NULL),
       defer_draw_scheduling_(false),
+      block_drawing_(false),
       waiting_on_compositing_end_(false),
       draw_on_compositing_end_(false),
       swap_state_(SWAP_NONE),
@@ -187,6 +188,19 @@ void Compositor::ScheduleDraw() {
   }
 }
 
+void Compositor::SetBlockDrawing(bool block_drawing) {
+  DCHECK(!compositor_thread_loop_);
+
+  if (block_drawing_ == block_drawing)
+    return;
+
+  block_drawing_ = block_drawing;
+  defer_draw_scheduling_ = block_drawing;
+
+  if (!block_drawing)
+    ScheduleDraw();
+}
+
 void Compositor::SetRootLayer(Layer* root_layer) {
   if (root_layer_ == root_layer)
     return;
@@ -208,6 +222,9 @@ void Compositor::SetHostHasTransparentBackground(
 void Compositor::Draw() {
   DCHECK(!compositor_thread_loop_.get());
 
+  if (block_drawing_)
+    return;
+
   defer_draw_scheduling_ = false;
   if (waiting_on_compositing_end_) {
     draw_on_compositing_end_ = true;