Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_coding/test/TwoWayCommunication.cc

 /*
  *  Copyright (c) 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 56 matching lines @@
   uint8_t noCodec = tmpACM->NumberOfCodecs();
   CodecInst codecInst;
   printf("List of Supported Codecs\n");
   printf("========================\n");
   for (uint8_t codecCntr = 0; codecCntr < noCodec; codecCntr++) {
     EXPECT_EQ(tmpACM->Codec(codecCntr, &codecInst), 0);
     printf("%d- %s\n", codecCntr, codecInst.plname);
   }
   printf("\nChoose a send codec for side A [0]: ");
   char myStr[15] = "";
-  EXPECT_TRUE(fgets(myStr, 10, stdin) != NULL);
+  EXPECT_TRUE(fgets(myStr, 10, stdin) != nullptr);
   *codecID_A = (uint8_t) atoi(myStr);
 
   printf("\nChoose a send codec for side B [0]: ");
-  EXPECT_TRUE(fgets(myStr, 10, stdin) != NULL);
+  EXPECT_TRUE(fgets(myStr, 10, stdin) != nullptr);
   *codecID_B = (uint8_t) atoi(myStr);
 
   printf("\n");
 }
 
 void TwoWayCommunication::SetUp() {
   uint8_t codecID_A;
   uint8_t codecID_B;
 
   ChooseCodec(&codecID_A, &codecID_B);
@@ skipping 209 matching lines @@
       EXPECT_EQ(0, _acmA->InitializeReceiver());
     // Re-register codec on side A.
     if (((secPassed % 7) == 6) && (msecPassed >= 990)) {
       EXPECT_EQ(true, _acmA->RegisterReceiveCodec(
                           codecInst_B->pltype, CodecInstToSdp(*codecInst_B)));
     }
   }
 }
 
 }  // namespace webrtc