Revert of Split iOS sdk in to separate targets

webrtc/sdk/objc/Framework/Classes/PeerConnection/RTCAudioSource.mm

-/*
- *  Copyright 2016 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 "RTCAudioSource+Private.h"
-
-#include "webrtc/base/checks.h"
-
-@implementation RTCAudioSource {
-}
-
-@synthesize volume = _volume;
-@synthesize nativeAudioSource = _nativeAudioSource;
-
-- (instancetype)initWithNativeAudioSource:
-    (rtc::scoped_refptr<webrtc::AudioSourceInterface>)nativeAudioSource {
-  RTC_DCHECK(nativeAudioSource);
-  if (self = [super initWithNativeMediaSource:nativeAudioSource
-                                         type:RTCMediaSourceTypeAudio]) {
-    _nativeAudioSource = nativeAudioSource;
-  }
-  return self;
-}
-
-- (instancetype)initWithNativeMediaSource:
-    (rtc::scoped_refptr<webrtc::MediaSourceInterface>)nativeMediaSource
-                                     type:(RTCMediaSourceType)type {
-  RTC_NOTREACHED();
-  return nil;
-}
-
-- (NSString *)description {
-  NSString *stateString = [[self class] stringForState:self.state];
-  return [NSString stringWithFormat:@"RTCAudioSource( %p ): %@", self, stateString];
-}
-
-- (void)setVolume:(double)volume {
-  _volume = volume;
-  _nativeAudioSource->SetVolume(volume);
-}
-
-@end