Roll ffmpeg DEPS for security fix.

media/filters/video_cadence_estimator.cc

 // Copyright 2015 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.
 
 #include "media/filters/video_cadence_estimator.h"
 
 #include <algorithm>
 #include <cmath>
 #include <iterator>
 #include <limits>
@@ skipping 135 matching lines @@
 int VideoCadenceEstimator::GetCadenceForFrame(uint64_t frame_number) const {
   DCHECK(has_cadence());
   return cadence_[frame_number % cadence_.size()];
 }
 
 VideoCadenceEstimator::Cadence VideoCadenceEstimator::CalculateCadence(
     base::TimeDelta render_interval,
     base::TimeDelta frame_duration,
     base::TimeDelta max_acceptable_drift,
     base::TimeDelta* time_until_max_drift) const {
-  DCHECK_LT(max_acceptable_drift, minimum_time_until_max_drift_);
-
   // The perfect cadence is the number of render intervals per frame.
   const double perfect_cadence =
       frame_duration.InSecondsF() / render_interval.InSecondsF();
 
   // We want to construct a cadence pattern to approximate the perfect cadence
   // while ensuring error doesn't accumulate too quickly.
   const double drift_ratio = max_acceptable_drift.InSecondsF() /

[DaleCurtis, 2015/10/01 01:16:38]

Actually, maybe we want std::min(minimum_time_until_max_drift_) here. WDYT
Qiang?

                              minimum_time_until_max_drift_.InSecondsF();
   const double minimum_acceptable_cadence =
       perfect_cadence / (1.0 + drift_ratio);
   const double maximum_acceptable_cadence =
       perfect_cadence / (1.0 - drift_ratio);
 
   // We've arbitrarily chosen the maximum allowable cadence length as 5. It's
   // proven sufficient to support most standard frame and render rates, while
   // being small enough that small frame and render timing errors don't render
   // it useless.
@@ skipping 39 matching lines @@
 
   std::ostringstream os;
   os << "[";
   std::copy(cadence.begin(), cadence.end() - 1,
             std::ostream_iterator<int>(os, ":"));
   os << cadence.back() << "]";
   return os.str();
 }
 
 }  // namespace media