Replace NULL with nullptr in all C++ files.

webrtc/modules/video_coding/timing.cc

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 19 matching lines @@
       min_playout_delay_ms_(0),
       max_playout_delay_ms_(10000),
       jitter_delay_ms_(0),
       current_delay_ms_(0),
       last_decode_ms_(0),
       prev_frame_timestamp_(0),
       num_decoded_frames_(0),
       num_delayed_decoded_frames_(0),
       first_decoded_frame_ms_(-1),
       sum_missed_render_deadline_ms_(0) {
-  if (master_timing == NULL) {
+  if (master_timing == nullptr) {
     master_ = true;
     ts_extrapolator_ = new TimestampExtrapolator(clock_->TimeInMilliseconds());
   } else {
     ts_extrapolator_ = master_timing->ts_extrapolator_;
   }
 }
 
 VCMTiming::~VCMTiming() {
   UpdateHistograms();
   if (master_) {
@@ skipping 249 matching lines @@
   *max_decode_ms = RequiredDecodeTimeMs();
   *current_delay_ms = current_delay_ms_;
   *target_delay_ms = TargetDelayInternal();
   *jitter_buffer_ms = jitter_delay_ms_;
   *min_playout_delay_ms = min_playout_delay_ms_;
   *render_delay_ms = render_delay_ms_;
   return (num_decoded_frames_ > 0);
 }
 
 }  // namespace webrtc