Move talk/examples/* to webrtc/examples.

webrtc/examples/objc/AppRTCDemo/ARDSignalingChannel.h

+/*
+ *  Copyright 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 <Foundation/Foundation.h>
+
+#import "ARDSignalingMessage.h"
+
+typedef NS_ENUM(NSInteger, ARDSignalingChannelState) {
+  // State when disconnected.
+  kARDSignalingChannelStateClosed,
+  // State when connection is established but not ready for use.
+  kARDSignalingChannelStateOpen,
+  // State when connection is established and registered.
+  kARDSignalingChannelStateRegistered,
+  // State when connection encounters a fatal error.
+  kARDSignalingChannelStateError
+};
+
+@protocol ARDSignalingChannel;
+@protocol ARDSignalingChannelDelegate <NSObject>
+
+- (void)channel:(id<ARDSignalingChannel>)channel
+    didChangeState:(ARDSignalingChannelState)state;
+
+- (void)channel:(id<ARDSignalingChannel>)channel
+    didReceiveMessage:(ARDSignalingMessage *)message;
+
+@end
+
+@protocol ARDSignalingChannel <NSObject>
+
+@property(nonatomic, readonly) NSString *roomId;
+@property(nonatomic, readonly) NSString *clientId;
+@property(nonatomic, readonly) ARDSignalingChannelState state;
+@property(nonatomic, weak) id<ARDSignalingChannelDelegate> delegate;
+
+// Registers the channel for the given room and client id.
+- (void)registerForRoomId:(NSString *)roomId
+                 clientId:(NSString *)clientId;
+
+// Sends signaling message over the channel.
+- (void)sendMessage:(ARDSignalingMessage *)message;
+
+@end
+