Prepare to rename RTC_NOTREACHED to RTC_DCHECK_NOTREACHED

Add implementation of RTC_DCHECK_NOTREACHED equal to the RTC_NOTREACHED.
The new macros will replace the old one when old one's usage will be
removed. The idea of the renaming to provide a clear signal that this
is debug build only macros and will be stripped in the production build.

Bug: webrtc:9065
Change-Id: I4c35d8b03e74a4b3fd1ae75dba2f9c05643101db
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/237802
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35348}
diff --git a/modules/audio_coding/neteq/dsp_helper.cc b/modules/audio_coding/neteq/dsp_helper.cc
index 54ec556..a979f94 100644
--- a/modules/audio_coding/neteq/dsp_helper.cc
+++ b/modules/audio_coding/neteq/dsp_helper.cc
@@ -354,7 +354,7 @@
       break;
     }
     default: {
-      RTC_NOTREACHED();
+      RTC_DCHECK_NOTREACHED();
       return -1;
     }
   }
diff --git a/modules/audio_coding/neteq/dtmf_tone_generator.cc b/modules/audio_coding/neteq/dtmf_tone_generator.cc
index 49cbf8f..9061e27 100644
--- a/modules/audio_coding/neteq/dtmf_tone_generator.cc
+++ b/modules/audio_coding/neteq/dtmf_tone_generator.cc
@@ -119,7 +119,7 @@
   } else if (fs == 48000) {
     fs_index = 3;
   } else {
-    RTC_NOTREACHED();
+    RTC_DCHECK_NOTREACHED();
     fs_index = 1;  // Default to 8000 Hz.
   }
 
diff --git a/modules/audio_coding/neteq/merge.cc b/modules/audio_coding/neteq/merge.cc
index ca5ec22..22cf6a7 100644
--- a/modules/audio_coding/neteq/merge.cc
+++ b/modules/audio_coding/neteq/merge.cc
@@ -372,7 +372,7 @@
   while (((best_correlation_index + input_length) <
           (timestamps_per_call_ + expand_->overlap_length())) ||
          ((best_correlation_index + input_length) < start_position)) {
-    RTC_NOTREACHED();                         // Should never happen.
+    RTC_DCHECK_NOTREACHED();                  // Should never happen.
     best_correlation_index += expand_period;  // Jump one lag ahead.
   }
   return best_correlation_index;
diff --git a/modules/audio_coding/neteq/neteq_impl.cc b/modules/audio_coding/neteq/neteq_impl.cc
index 6107b17..7e3c4ef 100644
--- a/modules/audio_coding/neteq/neteq_impl.cc
+++ b/modules/audio_coding/neteq/neteq_impl.cc
@@ -221,7 +221,7 @@
       break;
     }
     default:
-      RTC_NOTREACHED();
+      RTC_DCHECK_NOTREACHED();
   }
   if (!vad_enabled) {
     // Always set kVadUnknown when receive VAD is inactive.
@@ -894,7 +894,7 @@
     }
     case Operation::kUndefined: {
       RTC_LOG(LS_ERROR) << "Invalid operation kUndefined.";
-      RTC_NOTREACHED();  // This should not happen.
+      RTC_DCHECK_NOTREACHED();  // This should not happen.
       last_mode_ = Mode::kError;
       return kInvalidOperation;
     }
@@ -1057,7 +1057,7 @@
       // Don't use this packet, discard it.
       if (packet_buffer_->DiscardNextPacket(stats_.get()) !=
           PacketBuffer::kOK) {
-        RTC_NOTREACHED();  // Must be ok by design.
+        RTC_DCHECK_NOTREACHED();  // Must be ok by design.
       }
       // Check buffer again.
       if (!new_codec_) {
@@ -1877,7 +1877,7 @@
   //    // it must be copied to the speech buffer.
   //    // TODO(hlundin): This code seems incorrect. (Legacy.) Write test and
   //    // verify correct operation.
-  //    RTC_NOTREACHED();
+  //    RTC_DCHECK_NOTREACHED();
   //    // Must generate enough data to replace all of the `sync_buffer_`
   //    // "future".
   //    int required_length = sync_buffer_->FutureLength();
@@ -1967,7 +1967,8 @@
     next_packet = nullptr;
     if (!packet) {
       RTC_LOG(LS_ERROR) << "Should always be able to extract a packet here";
-      RTC_NOTREACHED();  // Should always be able to extract a packet here.
+      RTC_DCHECK_NOTREACHED();  // Should always be able to extract a packet
+                                // here.
       return -1;
     }
     const uint64_t waiting_time_ms = packet->waiting_time->ElapsedMs();
@@ -2001,7 +2002,7 @@
     } else if (!has_cng_packet) {
       RTC_LOG(LS_WARNING) << "Unknown payload type "
                           << static_cast<int>(packet->payload_type);
-      RTC_NOTREACHED();
+      RTC_DCHECK_NOTREACHED();
     }
 
     if (packet_duration == 0) {
diff --git a/modules/audio_coding/neteq/sync_buffer.cc b/modules/audio_coding/neteq/sync_buffer.cc
index 80e1691..7d7cac7 100644
--- a/modules/audio_coding/neteq/sync_buffer.cc
+++ b/modules/audio_coding/neteq/sync_buffer.cc
@@ -28,7 +28,7 @@
     next_index_ -= samples_added;
   } else {
     // This means that we are pushing out future data that was never used.
-    //    RTC_NOTREACHED();
+    //    RTC_DCHECK_NOTREACHED();
     // TODO(hlundin): This assert must be disabled to support 60 ms frames.
     // This should not happen even for 60 ms frames, but it does. Investigate
     // why.
diff --git a/modules/audio_coding/neteq/tools/rtp_encode.cc b/modules/audio_coding/neteq/tools/rtp_encode.cc
index 204f169..ee392f2 100644
--- a/modules/audio_coding/neteq/tools/rtp_encode.cc
+++ b/modules/audio_coding/neteq/tools/rtp_encode.cc
@@ -191,7 +191,7 @@
       config.sample_rate_hz = 48000;
       return config;
     default:
-      RTC_NOTREACHED();
+      RTC_DCHECK_NOTREACHED();
       return config;
   }
 }
@@ -242,7 +242,7 @@
           GetCodecConfig<AudioEncoderIsac>(), payload_type);
     }
   }
-  RTC_NOTREACHED();
+  RTC_DCHECK_NOTREACHED();
   return nullptr;
 }
 
@@ -259,7 +259,7 @@
       case 48000:
         return 100;
       default:
-        RTC_NOTREACHED();
+        RTC_DCHECK_NOTREACHED();
     }
     return 0;
   };