Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_coding/neteq/test/neteq_opus_quality_test.cc

 /*
  *  Copyright (c) 2014 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 105 matching lines @@
   int target_loss_rate_;
   int sub_packets_;
   int application_;
 };
 
 NetEqOpusQualityTest::NetEqOpusQualityTest()
     : NetEqQualityTest(kOpusBlockDurationMs * FLAGS_sub_packets,
                        kOpusSamplingKhz,
                        kOpusSamplingKhz,
                        NetEqDecoder::kDecoderOpus),
-      opus_encoder_(NULL),
-      repacketizer_(NULL),
+      opus_encoder_(nullptr),
+      repacketizer_(nullptr),
       sub_block_size_samples_(
           static_cast<size_t>(kOpusBlockDurationMs * kOpusSamplingKhz)),
       bit_rate_kbps_(FLAGS_bit_rate_kbps),
       fec_(FLAGS_fec),
       dtx_(FLAGS_dtx),
       complexity_(FLAGS_complexity),
       maxplaybackrate_(FLAGS_maxplaybackrate),
       target_loss_rate_(FLAGS_reported_loss_rate),
       sub_packets_(FLAGS_sub_packets) {
   // Redefine decoder type if input is stereo.
@@ skipping 67 matching lines @@
   EXPECT_GE(value, 0);
   return value;
 }
 
 TEST_F(NetEqOpusQualityTest, Test) {
   Simulate();
 }
 
 }  // namespace test
 }  // namespace webrtc