Add Media Router JS Gin module.

extensions/renderer/dispatcher.cc

Index: extensions/renderer/dispatcher.cc
diff --git a/extensions/renderer/dispatcher.cc b/extensions/renderer/dispatcher.cc
index f210e27e2b0f290c16be549822ba72fb78076561..5c24af143f1303ffcd4817b31f09132cdc3e6198 100644
--- a/extensions/renderer/dispatcher.cc
+++ b/extensions/renderer/dispatcher.cc
@@ -591,6 +591,14 @@ std::vector<std::pair<std::string, int> > Dispatcher::GetJsResources() {
   // Platform app sources that are not API-specific..
   resources.push_back(std::make_pair("platformApp", IDR_PLATFORM_APP_JS));
 
+#if defined(ENABLE_MEDIA_ROUTER)
+  resources.push_back(
+      std::make_pair("chrome/browser/media/router/media_router.mojom",
+                     IDR_MEDIA_ROUTER_MOJOM_JS));
+  resources.push_back(
+      std::make_pair("media_router_bindings", IDR_MEDIA_ROUTER_BINDINGS_JS));
+#endif  // defined(ENABLE_MEDIA_ROUTER)
+
   return resources;
 }