Make disable vsync run the renderer independently

cc/scheduler/scheduler_settings.h

Index: cc/scheduler/scheduler_settings.h
diff --git a/cc/scheduler/scheduler_settings.h b/cc/scheduler/scheduler_settings.h
index bc047179444b5e0f283eee54cf2005d242c0457b..b334c8e02c5aee543af70d7e9955e67d623c7f13 100644
--- a/cc/scheduler/scheduler_settings.h
+++ b/cc/scheduler/scheduler_settings.h
@@ -26,13 +26,11 @@ class CC_EXPORT SchedulerSettings {
   SchedulerSettings(const SchedulerSettings& other);
   ~SchedulerSettings();
 
-  bool use_external_begin_frame_source;

[enne (OOO), 2016/09/08 22:19:52]

Unused, so removed this too as I had to modify scheduler_unittest to handle
removing throttle_frame_production.

   bool main_frame_while_swap_throttled_enabled;
   bool main_frame_before_activation_enabled;
   bool commit_to_active_tree;
   bool timeout_and_draw_when_animation_checkerboards;
   bool using_synchronous_renderer_compositor;
-  bool throttle_frame_production;
   bool abort_commit_before_output_surface_creation;
 
   int maximum_number_of_failed_draws_before_draw_is_forced;