Change Clock::SetMaxTime() to be safe even in the presence of slow pipelines.

media/base/clock.h

 // Copyright (c) 2012 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 MEDIA_BASE_CLOCK_H_
 #define MEDIA_BASE_CLOCK_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
@@ skipping 38 matching lines @@
   void SetPlaybackRate(float playback_rate);
 
   // Forcefully sets the media time to |current_time|. The second parameter is
   // the |max_time| that the clock should progress after a call to Play(). This
   // value is often the time of the end of the last frame buffered and decoded.
   //
   // These values are clamped to the duration of the video, which is initially
   // set to 0 (before SetDuration() is called).
   void SetTime(base::TimeDelta current_time, base::TimeDelta max_time);
 
-  // Sets the |max_time| to be returned by a call to Elapsed(). |max_time| must
-  // be greater than or equal to the current Elapsed() time.
+  // Sets the |max_time| to be returned by a call to Elapsed().
   void SetMaxTime(base::TimeDelta max_time);
 
   // Returns the current elapsed media time. Returns 0 if SetDuration() has
   // never been called.
   base::TimeDelta Elapsed();
 
   // Sets the duration of the video. Clock expects the duration will be set
   // exactly once.
   void SetDuration(base::TimeDelta duration);
 
@@ skipping 52 matching lines @@
 
   // Duration of the media.
   base::TimeDelta duration_;
 
   DISALLOW_COPY_AND_ASSIGN(Clock);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_CLOCK_H_