Replace NULL with nullptr in webrtc/video.

webrtc/video/video_quality_test.cc

 /*
  *  Copyright (c) 2015 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.
  */
 #include <stdio.h>
@@ skipping 916 matching lines @@
   } else {
     if (params_.video.clip_name.empty()) {
       capturer_.reset(test::VideoCapturer::Create(input, params_.common.width,
                                                   params_.common.height,
                                                   params_.common.fps, clock_));
     } else {
       capturer_.reset(test::FrameGeneratorCapturer::CreateFromYuvFile(
           input, test::ResourcePath(params_.video.clip_name, "yuv"),
           params_.common.width, params_.common.height, params_.common.fps,
           clock_));
-      ASSERT_TRUE(capturer_.get() != nullptr)
-          << "Could not create capturer for " << params_.video.clip_name
-          << ".yuv. Is this resource file present?";
+      ASSERT_TRUE(capturer_) << "Could not create capturer for "
+                             << params_.video.clip_name
+                             << ".yuv. Is this resource file present?";
     }
   }
 }
 
 void VideoQualityTest::RunWithAnalyzer(const Params& params) {
   params_ = params;
 
   // TODO(ivica): Merge with RunWithRenderer and use a flag / argument to
   // differentiate between the analyzer and the renderer case.
   CheckParams();
 
   FILE* graph_data_output_file = nullptr;
   if (!params_.analyzer.graph_data_output_filename.empty()) {
     graph_data_output_file =
         fopen(params_.analyzer.graph_data_output_filename.c_str(), "w");
-    RTC_CHECK(graph_data_output_file != nullptr)
+    RTC_CHECK(graph_data_output_file)
         << "Can't open the file " << params_.analyzer.graph_data_output_filename
         << "!";
   }
 
   Call::Config call_config;
   call_config.bitrate_config = params.common.call_bitrate_config;
   CreateCalls(call_config, call_config);
 
   test::LayerFilteringTransport send_transport(
       params.pipe, sender_call_.get(), kPayloadTypeVP8, kPayloadTypeVP9,
@@ skipping 132 matching lines @@
   video_send_stream_->Stop();
   receive_stream->Stop();
 
   call->DestroyVideoReceiveStream(receive_stream);
   call->DestroyVideoSendStream(video_send_stream_);
 
   transport.StopSending();
 }
 
 }  // namespace webrtc