Implement mac version of AppRTCDemo.

- Refactored and moved AppRTCDemo to support sharing AppRTC connection code between iOS and mac counterparts.
- Refactored OpenGL rendering code to be shared between iOS and mac counterparts.
- iOS AppRTCDemo now respects video aspect ratio.

BUG=2168
R=fischman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/17589004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6291 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/examples/objc/AppRTCDemo/GAEChannelClient.m b/talk/examples/objc/AppRTCDemo/GAEChannelClient.m
new file mode 100644
index 0000000..6146043
--- /dev/null
+++ b/talk/examples/objc/AppRTCDemo/GAEChannelClient.m
@@ -0,0 +1,167 @@
+/*
+ * libjingle
+ * Copyright 2013, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#import "GAEChannelClient.h"
+
+#import "RTCPeerConnectionFactory.h"
+
+#if TARGET_OS_IPHONE
+
+#import <UIKit/UIKit.h>
+
+@interface GAEChannelClient () <UIWebViewDelegate>
+
+@property(nonatomic, strong) UIWebView* webView;
+
+#else
+
+#import <WebKit/WebKit.h>
+
+@interface GAEChannelClient ()
+
+@property(nonatomic, strong) WebView* webView;
+
+#endif
+
+@property(nonatomic, assign) id<GAEMessageHandler> delegate;
+
+@end
+
+@implementation GAEChannelClient
+
+- (id)initWithToken:(NSString*)token delegate:(id<GAEMessageHandler>)delegate {
+  self = [super init];
+  if (self) {
+#if TARGET_OS_IPHONE
+    _webView = [[UIWebView alloc] init];
+    _webView.delegate = self;
+#else
+    _webView = [[WebView alloc] init];
+    _webView.policyDelegate = self;
+#endif
+    _delegate = delegate;
+    NSString* htmlPath =
+        [[NSBundle mainBundle] pathForResource:@"channel" ofType:@"html"];
+    NSURL* htmlUrl = [NSURL fileURLWithPath:htmlPath];
+    NSString* path = [NSString
+        stringWithFormat:@"%@?token=%@", [htmlUrl absoluteString], token];
+
+#if TARGET_OS_IPHONE
+    [_webView
+#else
+    [[_webView mainFrame]
+#endif
+        loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:path]]];
+  }
+  return self;
+}
+
+- (void)dealloc {
+#if TARGET_OS_IPHONE
+  _webView.delegate = nil;
+  [_webView stopLoading];
+#else
+  _webView.policyDelegate = nil;
+  [[_webView mainFrame] stopLoading];
+#endif
+}
+
+#if TARGET_OS_IPHONE
+#pragma mark - UIWebViewDelegate
+
+- (BOOL)webView:(UIWebView*)webView
+    shouldStartLoadWithRequest:(NSURLRequest*)request
+                navigationType:(UIWebViewNavigationType)navigationType {
+#else
+// WebPolicyDelegate is an informal delegate.
+#pragma mark - WebPolicyDelegate
+
+- (void)webView:(WebView*)webView
+    decidePolicyForNavigationAction:(NSDictionary*)actionInformation
+                            request:(NSURLRequest*)request
+                              frame:(WebFrame*)frame
+                   decisionListener:(id<WebPolicyDecisionListener>)listener {
+#endif
+  NSString* scheme = [request.URL scheme];
+  NSAssert(scheme, @"scheme is nil: %@", request);
+  if (![scheme isEqualToString:@"js-frame"]) {
+#if TARGET_OS_IPHONE
+    return YES;
+#else
+    [listener use];
+    return;
+#endif
+  }
+  dispatch_async(dispatch_get_main_queue(), ^{
+      NSString* queuedMessage = [webView
+          stringByEvaluatingJavaScriptFromString:@"popQueuedMessage();"];
+      NSAssert([queuedMessage length], @"Empty queued message from JS");
+
+      NSDictionary* queuedMessageDict =
+          [GAEChannelClient jsonStringToDictionary:queuedMessage];
+      NSString* method = queuedMessageDict[@"type"];
+      NSAssert(method, @"Missing method: %@", queuedMessageDict);
+      NSDictionary* payload = queuedMessageDict[@"payload"];  // May be nil.
+
+      if ([method isEqualToString:@"onopen"]) {
+        [self.delegate onOpen];
+      } else if ([method isEqualToString:@"onmessage"]) {
+        NSDictionary* payloadData =
+            [GAEChannelClient jsonStringToDictionary:payload[@"data"]];
+        [self.delegate onMessage:payloadData];
+      } else if ([method isEqualToString:@"onclose"]) {
+        [self.delegate onClose];
+      } else if ([method isEqualToString:@"onerror"]) {
+        NSNumber* codeNumber = payload[@"code"];
+        int code = [codeNumber intValue];
+        NSAssert([codeNumber isEqualToNumber:[NSNumber numberWithInt:code]],
+                 @"Unexpected non-integral code: %@", payload);
+        [self.delegate onError:code withDescription:payload[@"description"]];
+      } else {
+        NSAssert(NO, @"Invalid message sent from UIWebView: %@", queuedMessage);
+      }
+  });
+#if TARGET_OS_IPHONE
+  return NO;
+#else
+  [listener ignore];
+  return;
+#endif
+}
+
+#pragma mark - Private
+
++ (NSDictionary*)jsonStringToDictionary:(NSString*)str {
+  NSData* data = [str dataUsingEncoding:NSUTF8StringEncoding];
+  NSError* error;
+  NSDictionary* dict =
+      [NSJSONSerialization JSONObjectWithData:data options:0 error:&error];
+  NSAssert(!error, @"Invalid JSON? %@", str);
+  return dict;
+}
+
+@end