Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_processing/config_unittest.cc

 /*
  *  Copyright (c) 2013 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 "webrtc/modules/audio_processing/include/config.h"
@@ skipping 32 matching lines @@
   Config config;
   config.Set<MyExperiment>(new MyExperiment(5, 1));
   const MyExperiment& my_exp = config.Get<MyExperiment>();
   EXPECT_EQ(5, my_exp.factor);
   EXPECT_EQ(1, my_exp.offset);
 }
 
 TEST(Config, SetNullSetsTheOptionBackToDefault) {
   Config config;
   config.Set<MyExperiment>(new MyExperiment(5, 1));
-  config.Set<MyExperiment>(NULL);
+  config.Set<MyExperiment>(nullptr);
   const MyExperiment& my_exp = config.Get<MyExperiment>();
   EXPECT_EQ(MyExperiment::kDefaultFactor, my_exp.factor);
   EXPECT_EQ(MyExperiment::kDefaultOffset, my_exp.offset);
 }
 
 struct Algo1_CostFunction {
   static const ConfigOptionID identifier =
       ConfigOptionID::kAlgo1CostFunctionForTest;
   Algo1_CostFunction() {}
 
@@ skipping 10 matching lines @@
   }
 };
 
 TEST(Config, SupportsPolymorphism) {
   Config config;
   config.Set<Algo1_CostFunction>(new SqrCost());
   EXPECT_EQ(25, config.Get<Algo1_CostFunction>().cost(5));
 }
 }  // namespace
 }  // namespace webrtc