Don't call unconfigureWebRTCSession if setConfiguration fails. webrtc:7471

webrtc/modules/audio_device/ios/audio_device_ios.mm

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 733 matching lines @@
     }
   }
 
   if (should_uninitialize_audio_unit) {
     RTCLog(@"Uninitializing audio unit for UpdateAudioUnit");
     audio_unit_->Uninitialize();
     UnconfigureAudioSession();
   }
 }
 
-void AudioDeviceIOS::ConfigureAudioSession() {
+bool AudioDeviceIOS::ConfigureAudioSession() {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
   RTCLog(@"Configuring audio session.");
   if (has_configured_session_) {
     RTCLogWarning(@"Audio session already configured.");
-    return;
+    return false;
   }
   RTCAudioSession* session = [RTCAudioSession sharedInstance];
   [session lockForConfiguration];
-  [session configureWebRTCSession:nil];
+  bool success = [session configureWebRTCSession:nil];
   [session unlockForConfiguration];
-  has_configured_session_ = true;
-  RTCLog(@"Configured audio session.");
+  if (success) {

[tkchin_webrtc, 2017/04/21 20:36:11]

nit: can just set to has_configured_session_ above to avoid unneeded local var

+    has_configured_session_ = true;
+    RTCLog(@"Configured audio session.");
+  } else {
+    RTCLog(@"Failed to configure audio session.");
+  }
+  return success;
 }
 
 void AudioDeviceIOS::UnconfigureAudioSession() {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
   RTCLog(@"Unconfiguring audio session.");
   if (!has_configured_session_) {
     RTCLogWarning(@"Audio session already unconfigured.");
     return;
   }
   RTCAudioSession* session = [RTCAudioSession sharedInstance];
@@ skipping 54 matching lines @@
 
   // All I/O should be stopped or paused prior to deactivating the audio
   // session, hence we deactivate as last action.
   [session lockForConfiguration];
   UnconfigureAudioSession();
   [session endWebRTCSession:nil];
   [session unlockForConfiguration];
 }
 
 }  // namespace webrtc