Reland [Media Router] Custom Controls 3 - add plumbing through MRUI and MRWebUIMessageHandler

chrome/browser/ui/webui/media_router/media_router_ui.cc

Index: chrome/browser/ui/webui/media_router/media_router_ui.cc
diff --git a/chrome/browser/ui/webui/media_router/media_router_ui.cc b/chrome/browser/ui/webui/media_router/media_router_ui.cc
index 96ff4e614d12e2bb54a17105f1d5e349c70bcb2c..924e26a94dfd80d50b5f08d7887e5bc0983e8be5 100644
--- a/chrome/browser/ui/webui/media_router/media_router_ui.cc
+++ b/chrome/browser/ui/webui/media_router/media_router_ui.cc
@@ -31,6 +31,7 @@
 #include "chrome/browser/ui/webui/media_router/media_router_localized_strings_provider.h"
 #include "chrome/browser/ui/webui/media_router/media_router_resources_provider.h"
 #include "chrome/browser/ui/webui/media_router/media_router_webui_message_handler.h"
+#include "chrome/common/chrome_features.h"
 #include "chrome/common/media_router/issue.h"
 #include "chrome/common/media_router/media_route.h"
 #include "chrome/common/media_router/media_sink.h"
@@ -153,6 +154,22 @@ void MediaRouterUI::UIMediaRoutesObserver::OnRoutesUpdated(
   callback_.Run(routes, joinable_route_ids);
 }
 
+MediaRouterUI::UIMediaRouteControllerObserver::UIMediaRouteControllerObserver(
+    MediaRouterUI* ui,
+    scoped_refptr<MediaRouteController> controller)
+    : MediaRouteController::Observer(std::move(controller)), ui_(ui) {}
+MediaRouterUI::UIMediaRouteControllerObserver::
+    ~UIMediaRouteControllerObserver() {}
+
+void MediaRouterUI::UIMediaRouteControllerObserver::OnMediaStatusUpdated(
+    const MediaStatus& status) {
+  ui_->UpdateMediaRouteStatus(status);
+}
+
+void MediaRouterUI::UIMediaRouteControllerObserver::OnControllerInvalidated() {
+  ui_->OnRouteControllerInvalidated();
+}
+
 MediaRouterUI::MediaRouterUI(content::WebUI* web_ui)
     : ConstrainedWebDialogUI(web_ui),
       ui_initialized_(false),
@@ -760,6 +777,39 @@ void MediaRouterUI::UpdateMaxDialogHeight(int height) {
   handler_->UpdateMaxDialogHeight(height);
 }
 
+const MediaRouteController* MediaRouterUI::GetMediaRouteController() const {
+  return route_controller_observer_
+             ? route_controller_observer_->controller().get()
+             : nullptr;
+}
+
+void MediaRouterUI::OnMediaControllerUIAvailable(
+    const MediaRoute::Id& route_id) {
+  scoped_refptr<MediaRouteController> controller =
+      router_->GetRouteController(route_id);
+  if (!controller) {
+    DVLOG(1) << "Requested a route controller with an invalid route ID.";
+    return;
+  }
+  DVLOG_IF(1, route_controller_observer_)
+      << "Route controller observer unexpectedly exists.";
+  route_controller_observer_ =
+      base::MakeUnique<UIMediaRouteControllerObserver>(this, controller);
+}
+
+void MediaRouterUI::OnMediaControllerUIClosed() {
+  route_controller_observer_.reset();
+}
+
+void MediaRouterUI::OnRouteControllerInvalidated() {
+  route_controller_observer_.reset();
+  handler_->OnRouteControllerInvalidated();
+}
+
+void MediaRouterUI::UpdateMediaRouteStatus(const MediaStatus& status) {
+  handler_->UpdateMediaRouteStatus(status);
+}
+
 std::string MediaRouterUI::GetSerializedInitiatorOrigin() const {
   url::Origin origin = initiator_
                            ? url::Origin(initiator_->GetLastCommittedURL())