[chrome.displaySource] Implement software based H.264 video encoder.

extensions/renderer/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
 import("//extensions/extensions.gni")
 
 assert(enable_extensions)
 
 # GYP version: extensions/extensions.gyp:extensions_renderer
@@ skipping 14 matching lines @@
     "//components/guest_view/renderer",
     "//content:resources",
     "//extensions:extensions_resources",
     "//gin",
     "//mojo/edk/js",
     "//mojo/public/js",
     "//skia",
     "//third_party/WebKit/public:blink",
   ]
 
-  if (enable_wifi_display) {
+  if (proprietary_codecs && enable_wifi_display) {
     wifi_display_sources = rebase_path(
             extensions_gypi_values.extensions_renderer_sources_wifi_display,
             ".",
             "//extensions")
     sources += wifi_display_sources
 
-    deps += [ "//third_party/wds:libwds" ]
+    deps += [
+      "//third_party/openh264/openh264.gyp:openh264_encoder",
+      "//third_party/wds:libwds",
+    ]
   }
 }