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/time/time.h"
+#include "base/values.h"
 #include "cc/base/cc_export.h"
 
 namespace cc {
 
 struct CC_EXPORT BeginFrameArgs {
   // 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".
@@ skipping 13 matching lines @@
   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_ptr<base::Value> AsValue() const {
+    scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue);
+    state->SetString("type", "BeginFrameArgs");

[brianderson, 2014/05/07 17:20:16]

I don't think we use this "type" pattern anywhere else. Would it be more
flexible to have the caller clarify it if needed?

[mithro-old, 2014/05/07 22:02:32]

I'd really like to have a type field because then in telemetry we can then find
"all dictionaries of type BeginFrameArgs" easily.

Should this be moved into it's own change? This function (with a little bit of
extra code) can be used to make it possible to use BeginFrameArgs in
TRACE_EVENTs...

[brianderson, 2014/05/08 00:55:58]

Please split it out to a separate patch, yes. If you feel strongly about keeping
the type, I won't push it - I see value too in being able to search for such an
important type in traces.

[mithro-old, 2014/05/09 02:45:58]

Done.

+    state->SetInteger("frame_time_us", frame_time.ToInternalValue());
+    state->SetInteger("deadline_us", deadline.ToInternalValue());
+    state->SetInteger("interval_us", interval.InMicroseconds());
+    return state.PassAs<base::Value>();
+  }
+
   base::TimeTicks frame_time;
   base::TimeTicks deadline;
   base::TimeDelta interval;
 
  private:
   BeginFrameArgs(base::TimeTicks frame_time,
                  base::TimeTicks deadline,
                  base::TimeDelta interval);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_