Adds support for Bluetooth headsets to the iOS audio layer

webrtc/modules/utility/source/helpers_ios.mm

 /*
  *  Copyright (c) 2015 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.
  */
 
 #if defined(WEBRTC_IOS)
 
+#import <AVFoundation/AVFoundation.h>
 #import <Foundation/Foundation.h>
 #import <sys/sysctl.h>
 #import <UIKit/UIKit.h>
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/scoped_ptr.h"
 #include "webrtc/modules/utility/interface/helpers_ios.h"
 
 namespace webrtc {
@@ skipping 27 matching lines @@
   return true;
 }
 
 // TODO(henrika): see if it is possible to move to GetThreadName in
 // platform_thread.h and base it on pthread methods instead.
 std::string GetCurrentThreadDescription() {
   NSString* name = [NSString stringWithFormat:@"%@", [NSThread currentThread]];
   return StdStringFromNSString(name);
 }
 
+std::string GetAudioSessionCategory() {
+  NSString* category = [[AVAudioSession sharedInstance] category];
+  return StdStringFromNSString(category);
+}
+
 std::string GetSystemName() {
   NSString* osName = [[UIDevice currentDevice] systemName];
   return StdStringFromNSString(osName);
 }
 
 std::string GetSystemVersion() {
   NSString* osVersion = [[UIDevice currentDevice] systemVersion];
   return StdStringFromNSString(osVersion);
 }
 
@@ skipping 93 matching lines @@
   if (!raw_name.compare("x86_64"))
     return std::string("Simulator");
   LOG(LS_WARNING) << "Failed to find device name";
   return raw_name;
 }
 
 }  // namespace ios
 }  // namespace webrtc
 
 #endif  // defined(WEBRTC_IOS)