iOS HW H264 support.

webrtc/build/webrtc.gni

 # Copyright (c) 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("//build/config/arm.gni")
 import("//build/config/mips.gni")
@@ skipping 91 matching lines @@
   if (!is_ios && (current_cpu != "arm" || arm_version >= 7)) {
     rtc_use_openmax_dl = true
   } else {
     rtc_use_openmax_dl = false
   }
 
   # WebRTC builds ARM v7 Neon instruction set optimized code for both iOS and
   # Android, which is why we currently cannot use the variables in
   # //build/config/arm.gni (since it disables Neon for Android).
   rtc_build_armv7_neon = current_cpu == "arm" && arm_version >= 7
+
+  # Enable this to use HW H.264 encoder/decoder on iOS PeerConnections.
+  # Enabling this may break interop with Android clients that support H264.
+  rtc_use_objc_h264 = false
 }
 
 # Make it possible to provide custom locations for some libraries (move these
 # up into declare_args should we need to actually use them for the GN build).
 rtc_libvpx_dir = "//third_party/libvpx"
 rtc_libyuv_dir = "//third_party/libyuv"
 rtc_opus_dir = "//third_party/opus"