Adding gtest helpers for BeginFrameArgs.

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".
   static BeginFrameArgs Create(base::TimeTicks frame_time,
                                base::TimeTicks deadline,
                                base::TimeDelta interval);
-  static BeginFrameArgs CreateForSynchronousCompositor();
+  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 DefaultDeadlineAdjustment();
 
   // 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
@@ skipping 12 matching lines @@
 
  private:
   BeginFrameArgs(base::TimeTicks frame_time,
                  base::TimeTicks deadline,
                  base::TimeDelta interval);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_