Decoupling audio_device from Obj-C code

webrtc/modules/audio_device/BUILD.gn

 # 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.
 
 import("../../webrtc.gni")
 
@@ skipping 28 matching lines @@
 
       # See https://bugs.chromium.org/p/webrtc/issues/detail?id=6265
       # for -Wno-thread-safety-analysis
       "-Wno-thread-safety-analysis",
       "-Wno-unused-private-field",
     ]
   }
 }
 
 rtc_static_library("audio_device") {
+  if (is_ios || is_mac) {
+    sources = [
+      "noop.cc",

[kjellander_webrtc, 2017/08/16 12:46:16]

Add a comment about why this silly thing is needed.

+    ]
+  }
+  if (rtc_include_internal_audio_device && is_ios) {
+    public_deps = [
+      ":audio_device_ios",
+    ]
+  } else {
+    public_deps = [
+      ":audio_device_generic",
+    ]
+  }
+}
+
+if (rtc_include_internal_audio_device && is_ios) {
+  rtc_static_library("audio_device_ios") {
+    visibility = [ ":*" ]
+    sources = [
+      "ios/audio_device_ios.h",
+      "ios/audio_device_ios.mm",
+      "ios/audio_device_not_implemented_ios.mm",
+      "ios/audio_session_observer.h",
+      "ios/objc/RTCAudioSessionDelegateAdapter.h",
+      "ios/objc/RTCAudioSessionDelegateAdapter.mm",
+      "ios/voice_processing_audio_unit.h",
+      "ios/voice_processing_audio_unit.mm",
+    ]
+    libs = [
+      "AudioToolbox.framework",
+      "AVFoundation.framework",
+      "Foundation.framework",
+      "UIKit.framework",
+    ]
+    deps = [
+      "../../rtc_base:gtest_prod",
+      "../../rtc_base:rtc_base",
+      "../../sdk:objc_audio",
+      "../../sdk:objc_common",
+      "../../system_wrappers:metrics_api",
+    ]
+    public_deps = [
+      ":audio_device_generic",
+    ]
+    if (!build_with_chromium && is_clang) {
+      # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
+      suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
+    }
+  }
+}
+
+rtc_static_library("audio_device_generic") {
+  visibility = [ ":*" ]
   public_configs = [ ":audio_device_config" ]
 
   deps = [
     "..:module_api",
     "../..:webrtc_common",
     "../../common_audio",
     "../../rtc_base:rtc_base_approved",
     "../../rtc_base:rtc_task_queue",
     "../../system_wrappers",
     "../utility",
@@ skipping 109 matching lines @@
           # Needed for CoreGraphics:
           "ApplicationServices.framework",
 
           "AudioToolbox.framework",
           "CoreAudio.framework",
 
           # Needed for CGEventSourceKeyState in audio_device_mac.cc:
           "CoreGraphics.framework",
         ]
       }
-      if (is_ios) {
-        public_deps = [
-          "../../rtc_base:gtest_prod",
-          "../../rtc_base:rtc_base",
-          "../../sdk:objc_audio",
-          "../../sdk:objc_common",
-        ]
-        sources += [
-          "ios/audio_device_ios.h",
-          "ios/audio_device_ios.mm",
-          "ios/audio_device_not_implemented_ios.mm",
-          "ios/audio_session_observer.h",
-          "ios/objc/RTCAudioSessionDelegateAdapter.h",
-          "ios/objc/RTCAudioSessionDelegateAdapter.mm",
-          "ios/voice_processing_audio_unit.h",
-          "ios/voice_processing_audio_unit.mm",
-        ]
-        libs = [
-          "AudioToolbox.framework",
-          "AVFoundation.framework",
-          "Foundation.framework",
-          "UIKit.framework",
-        ]
-      }
       if (is_win) {
         sources += [
           "win/audio_device_core_win.cc",
           "win/audio_device_core_win.h",
         ]
         libs = [
           # Required for the built-in WASAPI AEC.
           "dmoguids.lib",
           "wmcodecdspuuid.lib",
           "amstrmid.lib",
@@ skipping 47 matching lines @@
     "include/mock_audio_transport.h",
   ]
   deps = [
     ":audio_device",
     "../../test:test_support",
   ]
   all_dependent_configs = [ ":mock_audio_device_config" ]
 }
 
 if (rtc_include_tests) {
+  # TODO(kthelgason): Reenable these tests on simulator.
+  # See bugs.webrtc.org/7812
+  if (is_ios && !use_ios_simulator) {
+    rtc_source_set("audio_device_ios_unittests") {
+      testonly = true
+      visibility = [ ":*" ]
+      sources = [
+        "ios/audio_device_unittest_ios.mm",
+      ]
+      deps = [
+        ":audio_device",
+        ":mock_audio_device",
+        "../../rtc_base:rtc_base_approved",
+        "../../sdk:objc_audio",
+        "../../system_wrappers",
+        "../../test:test_support",
+        "//testing/gmock",
+        "//third_party/ocmock",
+      ]
+      if (!build_with_chromium && is_clang) {
+        # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
+        suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
+      }
+    }
+  }
+
   rtc_source_set("audio_device_unittests") {
     testonly = true
 
     # Skip restricting visibility on mobile platforms since the tests on those
     # gets additional generated targets which would require many lines here to
     # cover (which would be confusing to read and hard to maintain).
     if (!is_android && !is_ios) {
       visibility = [ "..:modules_unittests" ]
     }
     sources = [
       "fine_audio_buffer_unittest.cc",
     ]
     deps = [
       ":audio_device",
       ":mock_audio_device",
       "../../rtc_base:rtc_base_approved",
-      "../../system_wrappers:system_wrappers",
+      "../../system_wrappers",
       "../../test:test_support",
       "../utility:utility",
       "//testing/gmock",
     ]
     if (is_linux || is_mac || is_win) {
       sources += [ "audio_device_unittest.cc" ]
     }
     if (is_android) {
       # Need to disable error due to the line in
       # base/android/jni_android.h triggering it:
       # const BASE_EXPORT jobject GetApplicationContext()
       # error: type qualifiers ignored on function return type
       cflags = [ "-Wno-ignored-qualifiers" ]
       sources += [
         "android/audio_device_unittest.cc",
         "android/audio_manager_unittest.cc",
         "android/ensure_initialized.cc",
         "android/ensure_initialized.h",
       ]
       deps += [
         "../../../base",
         "../../sdk/android:libjingle_peerconnection_java",
       ]
     }
-    if (is_ios && !use_ios_simulator) {
-      # TODO(kthelgason): Reenable these tests on simulator.
-      # See bugs.webrtc.org/7812
-      sources += [ "ios/audio_device_unittest_ios.mm" ]
-      deps += [ "//third_party/ocmock" ]
-    }
     if (!build_with_chromium && is_clang) {
       # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
       suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
     }
   }
 
   if (!is_ios) {
     # These tests do not work on ios, see
     # https://bugs.chromium.org/p/webrtc/issues/detail?id=4755
     rtc_executable("audio_device_tests") {
@@ skipping 26 matching lines @@
       "android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java",
       "android/java/src/org/webrtc/voiceengine/WebRtcAudioRecord.java",
       "android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java",
       "android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java",
     ]
     deps = [
       "../../rtc_base:base_java",
     ]
   }
 }