cc: Add main frame timing info to frame timing tracker.

cc/scheduler/scheduler.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_SCHEDULER_SCHEDULER_H_
 #define CC_SCHEDULER_SCHEDULER_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 135 matching lines @@
     return state_machine_.MainThreadIsInHighLatencyMode();
   }
   bool BeginImplFrameDeadlinePending() const {
     return !begin_impl_frame_deadline_task_.IsCancelled();
   }
 
   base::TimeTicks AnticipatedDrawTime() const;
 
   void NotifyBeginMainFrameStarted();
 
-  base::TimeTicks LastBeginImplFrameTime();
+  base::TimeTicks LastBeginImplFrameTime() const;
+  base::TimeTicks NextBeginImplFrameTimeIfRequested() const;

[mithro-old, 2015/03/11 04:01:33]

Why do you need the NextBeginImplFrameTime? At the moment the value you are
returning is a *extremely rough* approximate to the next BeginImplFrameTime
value.

[vmpstr, 2015/03/16 18:36:43]

The value that I need to get is the rAF time if rAF was scheduled this frame. I
understand that this is a rough estimate and a variety of things can cause the
actual raf time to be further (eg process being descheduled). Do you know of a
better estimate I can use short of actually scheduling a rAF only for the
purposes of getting this time?

 
   void SetDeferCommits(bool defer_commits);
 
   scoped_refptr<base::trace_event::ConvertableToTraceFormat> AsValue() const;
   void AsValueInto(base::trace_event::TracedValue* value) const override;
 
   void SetContinuousPainting(bool continuous_painting) {
     state_machine_.SetContinuousPainting(continuous_painting);
   }
 
@@ skipping 79 matching lines @@
 
   friend class SchedulerFrameSourcesConstructor;
   friend class TestSchedulerFrameSourcesConstructor;
 
   DISALLOW_COPY_AND_ASSIGN(Scheduler);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_H_