Build dynamic iOS SDK.

- Places most ObjC code into webrtc/sdk/objc instead.
- New gyp targets to build, strip and export symbols for dylib.
- Removes old script used to generate dylib.

BUG=

Review URL: https://codereview.webrtc.org/1903663002

Cr-Commit-Position: refs/heads/master@{#12524}

webrtc/sdk/objc/Framework/Classes/RTCPeerConnectionFactory.mm

@@ -0,0 +1,85 @@
+/*
+ *  Copyright 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.
+ */
+
+#import "RTCPeerConnectionFactory+Private.h"
+
+#import "NSString+StdString.h"
+#if defined(WEBRTC_IOS)
+#import "RTCAVFoundationVideoSource+Private.h"
+#endif
+#import "RTCAudioTrack+Private.h"
+#import "RTCMediaStream+Private.h"
+#import "RTCPeerConnection+Private.h"
+#import "RTCVideoSource+Private.h"
+#import "RTCVideoTrack+Private.h"
+
+@implementation RTCPeerConnectionFactory {
+  rtc::scoped_ptr<rtc::Thread> _signalingThread;
+  rtc::scoped_ptr<rtc::Thread> _workerThread;
+}
+
+@synthesize nativeFactory = _nativeFactory;
+
+- (instancetype)init {
+  if ((self = [super init])) {
+    _signalingThread.reset(new rtc::Thread());
+    BOOL result = _signalingThread->Start();
+    NSAssert(result, @"Failed to start signaling thread.");
+    _workerThread.reset(new rtc::Thread());
+    result = _workerThread->Start();
+    NSAssert(result, @"Failed to start worker thread.");
+
+    _nativeFactory = webrtc::CreatePeerConnectionFactory(
+        _workerThread.get(), _signalingThread.get(), nullptr, nullptr, nullptr);
+    NSAssert(_nativeFactory, @"Failed to initialize PeerConnectionFactory!");
+  }
+  return self;
+}
+
+- (RTCAVFoundationVideoSource *)avFoundationVideoSourceWithConstraints:
+    (nullable RTCMediaConstraints *)constraints {
+#if defined(WEBRTC_IOS)
+  return [[RTCAVFoundationVideoSource alloc] initWithFactory:self
+                                                 constraints:constraints];
+#else
+  return nil;
+#endif
+}
+
+- (RTCAudioTrack *)audioTrackWithTrackId:(NSString *)trackId {
+  return [[RTCAudioTrack alloc] initWithFactory:self
+                                        trackId:trackId];
+}
+
+- (RTCVideoTrack *)videoTrackWithSource:(RTCVideoSource *)source
+                                trackId:(NSString *)trackId {
+  return [[RTCVideoTrack alloc] initWithFactory:self
+                                         source:source
+                                        trackId:trackId];
+}
+
+- (RTCMediaStream *)mediaStreamWithStreamId:(NSString *)streamId {
+  return [[RTCMediaStream alloc] initWithFactory:self
+                                        streamId:streamId];
+}
+
+- (RTCPeerConnection *)peerConnectionWithConfiguration:
+    (RTCConfiguration *)configuration
+                                           constraints:
+    (RTCMediaConstraints *)constraints
+                                              delegate:
+    (nullable id<RTCPeerConnectionDelegate>)delegate {
+  return [[RTCPeerConnection alloc] initWithFactory:self
+                                      configuration:configuration
+                                        constraints:constraints
+                                           delegate:delegate];
+}
+
+@end