Replace NULL with nullptr in all C++ files.

webrtc/media/engine/webrtcvoiceengine_unittest.cc

 /*
  *  Copyright (c) 2008 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 2840 matching lines @@
 
 // Test that we properly clean up any streams that were added, even if
 // not explicitly removed.
 TEST_F(WebRtcVoiceEngineTestFake, StreamCleanup) {
   EXPECT_TRUE(SetupSendStream());
   SetSendParameters(send_parameters_);
   EXPECT_TRUE(AddRecvStream(1));
   EXPECT_TRUE(AddRecvStream(2));
   EXPECT_EQ(3, voe_.GetNumChannels());  // default channel + 2 added
   delete channel_;
-  channel_ = NULL;
+  channel_ = nullptr;
   EXPECT_EQ(0, voe_.GetNumChannels());
 }
 
 TEST_F(WebRtcVoiceEngineTestFake, TestAddRecvStreamFailWithZeroSsrc) {
   EXPECT_TRUE(SetupSendStream());
   EXPECT_FALSE(AddRecvStream(0));
 }
 
 TEST_F(WebRtcVoiceEngineTestFake, TestNoLeakingWhenAddRecvStreamFail) {
   EXPECT_TRUE(SetupChannel());
@@ skipping 871 matching lines @@
   // Without this cast, the comparison turned unsigned and, thus, failed for -1.
   const int num_specs = static_cast<int>(specs.size());
   EXPECT_GE(find_codec({"cn", 8000, 1}), num_specs);
   EXPECT_GE(find_codec({"cn", 16000, 1}), num_specs);
   EXPECT_EQ(find_codec({"cn", 32000, 1}), -1);
   EXPECT_GE(find_codec({"telephone-event", 8000, 1}), num_specs);
   EXPECT_GE(find_codec({"telephone-event", 16000, 1}), num_specs);
   EXPECT_GE(find_codec({"telephone-event", 32000, 1}), num_specs);
   EXPECT_GE(find_codec({"telephone-event", 48000, 1}), num_specs);
 }