[chromecast] Enable Mojo javascript bindings for cast_shell

chromecast/renderer/cast_content_renderer_client.cc

Index: chromecast/renderer/cast_content_renderer_client.cc
diff --git a/chromecast/renderer/cast_content_renderer_client.cc b/chromecast/renderer/cast_content_renderer_client.cc
index c73b8783343d3a4ddb5ded9695f7337f023eab1c..8894b89c10b443eccdf56c3e65644398f34db005 100644
--- a/chromecast/renderer/cast_content_renderer_client.cc
+++ b/chromecast/renderer/cast_content_renderer_client.cc
@@ -5,28 +5,38 @@
 #include "chromecast/renderer/cast_content_renderer_client.h"
 
 #include <stdint.h>
+#include <string>
 
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "chromecast/base/chromecast_switches.h"
 #include "chromecast/common/media/cast_media_client.h"
 #include "chromecast/crash/cast_crash_keys.h"
+#include "chromecast/renderer/cast_gin_runner.h"
 #include "chromecast/renderer/cast_media_load_deferrer.h"
 #include "chromecast/renderer/key_systems_cast.h"
 #include "chromecast/renderer/media/media_caps_observer_impl.h"
 #include "components/network_hints/renderer/prescient_networking_dispatcher.h"
+#include "content/grit/content_resources.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
+#include "gin/modules/module_registry.h"
+#include "gin/per_context_data.h"
+#include "gin/public/context_holder.h"
 #include "media/base/media.h"
 #include "services/shell/public/cpp/interface_provider.h"
 #include "third_party/WebKit/public/platform/WebColor.h"
 #include "third_party/WebKit/public/web/WebFrameWidget.h"
+#include "third_party/WebKit/public/web/WebKit.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebSettings.h"
 #include "third_party/WebKit/public/web/WebView.h"
+#include "ui/base/resource/resource_bundle.h"
 
 #if defined(OS_ANDROID)
 #include "media/base/android/media_codec_util.h"
@@ -128,5 +138,44 @@ void CastContentRendererClient::DeferMediaLoad(
   new CastMediaLoadDeferrer(render_frame, closure);
 }
 
+void CastContentRendererClient::RunScriptsAtDocumentStart(
+    content::RenderFrame* render_frame) {
+  // This method enables Mojo bindings in JavaScript for Chromecast.
+
+  v8::HandleScope handle_scope(blink::mainThreadIsolate());
+  v8::Local<v8::Context> context =
+      render_frame->GetWebFrame()->mainWorldScriptContext();
+
+  // CastGinRunner manages its own lifetime.
+  CastGinRunner* runner = new CastGinRunner(render_frame);
+  gin::Runner::Scope scoper(runner);
+
+  // Initialize AMD API for Mojo.
+  render_frame->EnsureMojoBuiltinsAreAvailable(context->GetIsolate(), context);
+  gin::ModuleRegistry::InstallGlobals(context->GetIsolate(), context->Global());
+
+  // Inject JavaScript files in the correct dependency order.
+  static const int mojo_resource_ids[] = {
+      IDR_MOJO_UNICODE_JS,
+      IDR_MOJO_BUFFER_JS,
+      IDR_MOJO_CODEC_JS,
+      IDR_MOJO_CONNECTOR_JS,
+      IDR_MOJO_VALIDATOR_JS,
+      IDR_MOJO_ROUTER_JS,
+      IDR_MOJO_BINDINGS_JS,
+      IDR_MOJO_CONNECTION_JS,
+  };
+  for (size_t i = 0; i < arraysize(mojo_resource_ids); i++) {
+    ExecuteJavaScript(render_frame, mojo_resource_ids[i]);
+  }
+}
+
+void ExecuteJavaScript(content::RenderFrame* render_frame, int resource_id) {
+  const std::string& js_string = ui::ResourceBundle::GetSharedInstance()
+                                     .GetRawDataResource(resource_id)
+                                     .as_string();
+  render_frame->ExecuteJavaScript(base::UTF8ToUTF16(js_string));
+}
+
 }  // namespace shell
 }  // namespace chromecast