Replace NULL with nullptr in all C++ files.

webrtc/modules/audio_processing/aec/echo_cancellation.cc

Index: webrtc/modules/audio_processing/aec/echo_cancellation.cc
diff --git a/webrtc/modules/audio_processing/aec/echo_cancellation.cc b/webrtc/modules/audio_processing/aec/echo_cancellation.cc
index 9261632c17d799df935a6fce20926b44d400ddc4..8a038ae3f4d7256683cc2dc8e1b70e7b2968876d 100644
--- a/webrtc/modules/audio_processing/aec/echo_cancellation.cc
+++ b/webrtc/modules/audio_processing/aec/echo_cancellation.cc
@@ -124,19 +124,19 @@ void* WebRtcAec_Create() {
   Aec* aecpc = new Aec();
 
   if (!aecpc) {
-    return NULL;
+    return nullptr;
   }
   aecpc->data_dumper.reset(new ApmDataDumper(aecpc->instance_count));
 
   aecpc->aec = WebRtcAec_CreateAec(aecpc->instance_count);
   if (!aecpc->aec) {
     WebRtcAec_Free(aecpc);
-    return NULL;
+    return nullptr;
   }
   aecpc->resampler = WebRtcAec_CreateResampler();
   if (!aecpc->resampler) {
     WebRtcAec_Free(aecpc);
-    return NULL;
+    return nullptr;
   }
   // Create far-end pre-buffer. The buffer size has to be large enough for
   // largest possible drift compensation (kResamplerBufferSize) + "almost" an
@@ -145,7 +145,7 @@ void* WebRtcAec_Create() {
       WebRtc_CreateBuffer(PART_LEN2 + kResamplerBufferSize, sizeof(float));
   if (!aecpc->far_pre_buf) {
     WebRtcAec_Free(aecpc);
-    return NULL;
+    return nullptr;
   }
 
   aecpc->initFlag = 0;
@@ -157,7 +157,7 @@ void* WebRtcAec_Create() {
 void WebRtcAec_Free(void* aecInst) {
   Aec* aecpc = reinterpret_cast<Aec*>(aecInst);
 
-  if (aecpc == NULL) {
+  if (aecpc == nullptr) {
     return;
   }
 
@@ -300,7 +300,7 @@ int32_t WebRtcAec_BufferFarend(void* aecInst,
   while (WebRtc_available_read(aecpc->far_pre_buf) >= PART_LEN2) {
     // We have enough data to pass to the FFT, hence read PART_LEN2 samples.
     {
-      float* ptmp = NULL;
+      float* ptmp = nullptr;
       float tmp[PART_LEN2];
       WebRtc_ReadBuffer(aecpc->far_pre_buf,
                         reinterpret_cast<void**>(&ptmp), tmp, PART_LEN2);
@@ -324,7 +324,7 @@ int32_t WebRtcAec_Process(void* aecInst,
   Aec* aecpc = reinterpret_cast<Aec*>(aecInst);
   int32_t retVal = 0;
 
-  if (out == NULL) {
+  if (out == nullptr) {
     return AEC_NULL_POINTER_ERROR;
   }
 
@@ -393,7 +393,7 @@ int WebRtcAec_set_config(void* handle, AecConfig config) {
 
 int WebRtcAec_get_echo_status(void* handle, int* status) {
   Aec* self = reinterpret_cast<Aec*>(handle);
-  if (status == NULL) {
+  if (status == nullptr) {
     return AEC_NULL_POINTER_ERROR;
   }
   if (self->initFlag != initCheck) {
@@ -414,10 +414,10 @@ int WebRtcAec_GetMetrics(void* handle, AecMetrics* metrics) {
   Stats erle;
   Stats a_nlp;
 
-  if (handle == NULL) {
+  if (handle == nullptr) {
     return -1;
   }
-  if (metrics == NULL) {
+  if (metrics == nullptr) {
     return AEC_NULL_POINTER_ERROR;
   }
   if (self->initFlag != initCheck) {
@@ -506,10 +506,10 @@ int WebRtcAec_GetDelayMetrics(void* handle,
                               int* std,
                               float* fraction_poor_delays) {
   Aec* self = reinterpret_cast<Aec*>(handle);
-  if (median == NULL) {
+  if (median == nullptr) {
     return AEC_NULL_POINTER_ERROR;
   }
-  if (std == NULL) {
+  if (std == nullptr) {
     return AEC_NULL_POINTER_ERROR;
   }
   if (self->initFlag != initCheck) {
@@ -526,7 +526,7 @@ int WebRtcAec_GetDelayMetrics(void* handle,
 
 AecCore* WebRtcAec_aec_core(void* handle) {
   if (!handle) {
-    return NULL;
+    return nullptr;
   }
   return reinterpret_cast<Aec*>(handle)->aec;
 }