Refactoring the way begin frame sources inside scheduler work.

cc/output/begin_frame_args.h

 // Copyright 2013 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_OUTPUT_BEGIN_FRAME_ARGS_H_
 #define CC_OUTPUT_BEGIN_FRAME_ARGS_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "cc/base/cc_export.h"
 
 namespace base {
 namespace debug {
 class ConvertableToTraceFormat;
 class TracedValue;
 }
 }
 
 namespace cc {
 
 struct CC_EXPORT BeginFrameArgs {
+  enum BeginFrameArgsType {
+    INVALID,
+    NORMAL,
+    SYNCHRONOUS,
+    MISSED,
+  };
+
   // Creates an invalid set of values.
   BeginFrameArgs();
 
   // You should be able to find all instances where a BeginFrame has been
   // created by searching for "BeginFrameArgs::Create".
   static BeginFrameArgs Create(base::TimeTicks frame_time,
                                base::TimeTicks deadline,
-                               base::TimeDelta interval);
+                               base::TimeDelta interval,
+                               BeginFrameArgsType type = NORMAL);

[brianderson, 2014/09/27 00:41:40]

Default values aren't allowed, but overloading is. Please make this a separate
function.

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Default_Argum...

[danakj, 2014/09/27 01:09:44]

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Function_Over...

But if you're going to overload consider making the name slightly different is
the advice of the guide, which I think really helps.

[mithro-old, 2014/09/30 08:30:01]

Someone should fix CreateForSynchronousCompositor below.

[mithro-old, 2014/09/30 08:30:01]

Done.

   static BeginFrameArgs CreateForSynchronousCompositor(
       base::TimeTicks now = base::TimeTicks());
 
   // This is the default delta that will be used to adjust the deadline when
   // proper draw-time estimations are not yet available.
   static base::TimeDelta DefaultEstimatedParentDrawTime();
 
   // This is the default interval to use to avoid sprinkling the code with
   // magic numbers.
   static base::TimeDelta DefaultInterval();
 
   // This is the default amount of time after the frame_time to retroactively
   // send a BeginFrame that had been skipped. This only has an effect if the
   // deadline has passed, since the deadline is also used to trigger BeginFrame
   // retroactively.
   static base::TimeDelta DefaultRetroactiveBeginFramePeriod();
 
   bool IsValid() const { return interval >= base::TimeDelta(); }
 
   scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
   void AsValueInto(base::debug::TracedValue* dict) const;
 
   base::TimeTicks frame_time;
   base::TimeTicks deadline;
   base::TimeDelta interval;
+  BeginFrameArgsType type;
 
  private:
   BeginFrameArgs(base::TimeTicks frame_time,
                  base::TimeTicks deadline,
-                 base::TimeDelta interval);
+                 base::TimeDelta interval,
+                 BeginFrameArgsType type);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_