Replace NULL with nullptr in all C++ files.

webrtc/pc/test/fakeaudiocapturemodule_unittest.cc

 /*
  *  Copyright 2012 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 15 matching lines @@
 
   FakeAdmTest()
       : push_iterations_(0),
         pull_iterations_(0),
         rec_buffer_bytes_(0) {
     memset(rec_buffer_, 0, sizeof(rec_buffer_));
   }
 
   void SetUp() override {
     fake_audio_capture_module_ = FakeAudioCaptureModule::Create();
-    EXPECT_TRUE(fake_audio_capture_module_.get() != NULL);
+    EXPECT_TRUE(fake_audio_capture_module_.get() != nullptr);
   }
 
   // Callbacks inherited from webrtc::AudioTransport.
   // ADM is pushing data.
   int32_t RecordedDataIsAvailable(const void* audioSamples,
                                   const size_t nSamples,
                                   const size_t nBytesPerSample,
                                   const size_t nChannels,
                                   const uint32_t samplesPerSec,
                                   const uint32_t totalDelayMS,
@@ skipping 158 matching lines @@
 
   EXPECT_EQ(0, fake_audio_capture_module_->InitRecording());
   EXPECT_EQ(0, fake_audio_capture_module_->StartRecording());
 
   EXPECT_TRUE_WAIT(push_iterations() > 0, kMsInSecond);
   EXPECT_TRUE_WAIT(pull_iterations() > 0, kMsInSecond);
 
   EXPECT_EQ(0, fake_audio_capture_module_->StopPlayout());
   EXPECT_EQ(0, fake_audio_capture_module_->StopRecording());
 }