Remove AudioProcessing::ChannelLayout

This enum is no longer needed. Also moving the last piece of code from
common.h to audio_processing_impl.h, allowing to delete common.h.

Bug: chromium:1271981, b/217349489
Change-Id: If115336c36d6d7b5845a903e421c18aebfe434ee
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/251242
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Commit-Queue: Henrik Lundin <henrik.lundin@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35946}
diff --git a/modules/audio_processing/BUILD.gn b/modules/audio_processing/BUILD.gn
index 98e0db5..f32058d 100644
--- a/modules/audio_processing/BUILD.gn
+++ b/modules/audio_processing/BUILD.gn
@@ -146,7 +146,6 @@
     "audio_processing_builder_impl.cc",
     "audio_processing_impl.cc",
     "audio_processing_impl.h",
-    "common.h",
     "echo_control_mobile_impl.cc",
     "echo_control_mobile_impl.h",
     "gain_control_impl.cc",
diff --git a/modules/audio_processing/audio_processing_impl.cc b/modules/audio_processing/audio_processing_impl.cc
index 754abca..8810efe 100644
--- a/modules/audio_processing/audio_processing_impl.cc
+++ b/modules/audio_processing/audio_processing_impl.cc
@@ -24,7 +24,6 @@
 #include "common_audio/include/audio_util.h"
 #include "modules/audio_processing/aec_dump/aec_dump_factory.h"
 #include "modules/audio_processing/audio_buffer.h"
-#include "modules/audio_processing/common.h"
 #include "modules/audio_processing/include/audio_frame_view.h"
 #include "modules/audio_processing/logging/apm_data_dumper.h"
 #include "modules/audio_processing/optionally_built_submodule_creators.h"
diff --git a/modules/audio_processing/audio_processing_impl.h b/modules/audio_processing/audio_processing_impl.h
index 32797df..47dd62e 100644
--- a/modules/audio_processing/audio_processing_impl.h
+++ b/modules/audio_processing/audio_processing_impl.h
@@ -51,6 +51,10 @@
 class ApmDataDumper;
 class AudioConverter;
 
+constexpr int RuntimeSettingQueueSize() {
+  return 100;
+}
+
 class AudioProcessingImpl : public AudioProcessing {
  public:
   // Methods forcing APM to run in a single-threaded manner.
diff --git a/modules/audio_processing/audio_processing_impl_unittest.cc b/modules/audio_processing/audio_processing_impl_unittest.cc
index 1e58e5b..33d46fb 100644
--- a/modules/audio_processing/audio_processing_impl_unittest.cc
+++ b/modules/audio_processing/audio_processing_impl_unittest.cc
@@ -14,7 +14,6 @@
 #include <memory>
 
 #include "api/scoped_refptr.h"
-#include "modules/audio_processing/common.h"
 #include "modules/audio_processing/include/audio_processing.h"
 #include "modules/audio_processing/optionally_built_submodule_creators.h"
 #include "modules/audio_processing/test/audio_processing_builder_for_testing.h"
diff --git a/modules/audio_processing/audio_processing_unittest.cc b/modules/audio_processing/audio_processing_unittest.cc
index 1189639..96e2d84 100644
--- a/modules/audio_processing/audio_processing_unittest.cc
+++ b/modules/audio_processing/audio_processing_unittest.cc
@@ -27,7 +27,6 @@
 #include "common_audio/signal_processing/include/signal_processing_library.h"
 #include "modules/audio_processing/aec_dump/aec_dump_factory.h"
 #include "modules/audio_processing/audio_processing_impl.h"
-#include "modules/audio_processing/common.h"
 #include "modules/audio_processing/include/mock_audio_processing.h"
 #include "modules/audio_processing/test/audio_processing_builder_for_testing.h"
 #include "modules/audio_processing/test/protobuf_utils.h"
diff --git a/modules/audio_processing/common.h b/modules/audio_processing/common.h
deleted file mode 100644
index e14279e..0000000
--- a/modules/audio_processing/common.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- *  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.
- */
-
-#ifndef MODULES_AUDIO_PROCESSING_COMMON_H_
-#define MODULES_AUDIO_PROCESSING_COMMON_H_
-
-#include "modules/audio_processing/include/audio_processing.h"
-#include "rtc_base/checks.h"
-
-namespace webrtc {
-
-constexpr int RuntimeSettingQueueSize() {
-  return 100;
-}
-
-static inline size_t ChannelsFromLayout(AudioProcessing::ChannelLayout layout) {
-  switch (layout) {
-    case AudioProcessing::kMono:
-    case AudioProcessing::kMonoAndKeyboard:
-      return 1;
-    case AudioProcessing::kStereo:
-    case AudioProcessing::kStereoAndKeyboard:
-      return 2;
-  }
-  RTC_DCHECK_NOTREACHED();
-  return 0;
-}
-
-}  // namespace webrtc
-
-#endif  // MODULES_AUDIO_PROCESSING_COMMON_H_
diff --git a/modules/audio_processing/include/audio_processing.h b/modules/audio_processing/include/audio_processing.h
index 6282633..8af5013 100644
--- a/modules/audio_processing/include/audio_processing.h
+++ b/modules/audio_processing/include/audio_processing.h
@@ -385,17 +385,6 @@
     std::string ToString() const;
   };
 
-  // TODO(mgraczyk): Remove once all methods that use ChannelLayout are gone.
-  enum ChannelLayout {
-    kMono,
-    // Left, right.
-    kStereo,
-    // Mono, keyboard, and mic.
-    kMonoAndKeyboard,
-    // Left, right, keyboard, and mic.
-    kStereoAndKeyboard
-  };
-
   // Specifies the properties of a setting to be passed to AudioProcessing at
   // runtime.
   class RuntimeSetting {
diff --git a/modules/audio_processing/test/test_utils.cc b/modules/audio_processing/test/test_utils.cc
index 839358d..dcd5869 100644
--- a/modules/audio_processing/test/test_utils.cc
+++ b/modules/audio_processing/test/test_utils.cc
@@ -139,15 +139,4 @@
       AudioProcessing::kChunkSizeMs * sample_rate_hz / 1000;
 }
 
-AudioProcessing::ChannelLayout LayoutFromChannels(size_t num_channels) {
-  switch (num_channels) {
-    case 1:
-      return AudioProcessing::kMono;
-    case 2:
-      return AudioProcessing::kStereo;
-    default:
-      RTC_CHECK_NOTREACHED();
-  }
-}
-
 }  // namespace webrtc
diff --git a/modules/audio_processing/test/test_utils.h b/modules/audio_processing/test/test_utils.h
index aa13211..de0fc11 100644
--- a/modules/audio_processing/test/test_utils.h
+++ b/modules/audio_processing/test/test_utils.h
@@ -154,8 +154,6 @@
   cb->reset(new ChannelBuffer<T>(frame->samples_per_channel, num_channels));
 }
 
-AudioProcessing::ChannelLayout LayoutFromChannels(size_t num_channels);
-
 template <typename T>
 float ComputeSNR(const T* ref, const T* test, size_t length, float* variance) {
   float mse = 0;