GN: Add targets for AppRTCDemo on Mac+iOS

webrtc/sdk/BUILD.gn

 # 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("../build/webrtc.gni")
 import("//build_overrides/webrtc.gni")
@@ skipping 168 matching lines @@
     ]
 
     public_configs = [ ":rtc_sdk_common_objc_config" ]
 
     if (is_clang) {
       # Suppress warnings from the Chromium Clang plugins.
       # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
       configs -= [ "//build/config/clang:find_bad_constructs" ]
     }
 
-    libs += [
-      "AVFoundation.framework",
-      "stdc++",
-    ]
+    libs += [ "AVFoundation.framework" ]
 
     deps = [
       ":rtc_sdk_common_objc",
       "../api:libjingle_peerconnection",
     ]
   }
 
   # TODO(tkchin): Add the rtc_sdk_framework_objc target.
 }