H.264 video codec support using OpenH264/FFmpeg

webrtc/build/common.gypi

Index: webrtc/build/common.gypi
diff --git a/webrtc/build/common.gypi b/webrtc/build/common.gypi
index 4c2522e483749d84a1908ad227342650c7107d22..7791c58ad72d6cdc8ff1e8e6edffc64a2c868265 100644
--- a/webrtc/build/common.gypi
+++ b/webrtc/build/common.gypi
@@ -125,9 +125,14 @@
     'build_with_neon%': 0,
 
     # Enable this to use HW H.264 encoder/decoder on iOS/Mac PeerConnections.
-    # Enabling this may break interop with Android clients that support H264.
+    # Enabling this may break interop with Android clients that support H.264.
     'use_objc_h264%': 0,
 
+    # Enable this to build OpenH264 SW H.264 encoder/decoder.
+    # CHECK THE OPENH264 LICENCE BEFORE BUILDING, YOU MAY LIABLE TO PAY

[hta - Chromium, 2015/10/01 09:45:51]

Grammar nit: YOU MAY LIABLE -> YOU MAY BE LIABLE
My sense of "don't say too much" says that we should just say CHECK THE OPENH264
LICENSE BEFORE BUILDING.

[hbos, 2015/10/01 12:19:45]

Done.

+    # LICENSING.
+    'use_openh264%': 0,
+
     'conditions': [
       ['build_with_chromium==1', {
         # Exclude pulse audio on Chromium since its prerequisites don't require
@@ -342,6 +347,11 @@
           'WEBRTC_OBJC_H264',
         ],
       }],
+      ['use_openh264==1', {
+        'defines': [
+          'WEBRTC_OPENH264',
+        ],
+      }],
       ['OS=="linux"', {
         'defines': [
           'WEBRTC_LINUX',