(Not for review) Dummy C++ side Custom Controls implementation

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 8e8e974063672381b1a29e92462627bebf12a0df..8bb7b4cf80c236a42c84a9013a1ff06ac6aa6644 100644
--- a/chrome/browser/ui/webui/media_router/media_router_ui.cc
+++ b/chrome/browser/ui/webui/media_router/media_router_ui.cc
@@ -29,6 +29,7 @@
 #include "chrome/browser/media/router/media_sinks_observer.h"
 #include "chrome/browser/media/router/media_source.h"
 #include "chrome/browser/media/router/media_source_helper.h"
+#include "chrome/browser/media/router/mojo/media_route_controller.h"
 #include "chrome/browser/media/router/mojo/media_router_mojo_impl.h"
 #include "chrome/browser/media/router/presentation_service_delegate_impl.h"
 #include "chrome/browser/media/router/route_request_result.h"
@@ -153,6 +154,16 @@ void MediaRouterUI::UIMediaRoutesObserver::OnRoutesUpdated(
   callback_.Run(routes, joinable_route_ids);
 }
 
+MediaRouterUI::UIMediaRouteStatusObserver::UIMediaRouteStatusObserver(
+    MediaRouterWebUIMessageHandler* handler)
+    : handler_(handler) {}
+MediaRouterUI::UIMediaRouteStatusObserver::~UIMediaRouteStatusObserver() {}
+
+void MediaRouterUI::UIMediaRouteStatusObserver::OnMediaRouteStatusUpdated(
+    const MediaStatus& status) {
+  handler_->UpdateMediaRouteStatus(status);
+}
+
 MediaRouterUI::MediaRouterUI(content::WebUI* web_ui)
     : ConstrainedWebDialogUI(web_ui),
       ui_initialized_(false),
@@ -211,6 +222,8 @@ MediaRouterUI::~MediaRouterUI() {
           "No screens found."));
     }
   }
+  if (route_controller_)
+    route_controller_->RemoveObserver(route_status_observer_.get());
 }
 
 void MediaRouterUI::InitWithDefaultMediaSource(
@@ -615,6 +628,11 @@ void MediaRouterUI::OnRoutesUpdated(
   if (ui_initialized_)
     handler_->UpdateRoutes(routes_, joinable_route_ids_,
                            routes_and_cast_modes_);
+
+  if (selected_route_ && !IsValidRouteId(selected_route_.value())) {
+    selected_route_.reset();
+    route_controller_ = nullptr;
+  }
 }
 
 void MediaRouterUI::OnRouteResponseReceived(
@@ -761,6 +779,56 @@ void MediaRouterUI::UpdateMaxDialogHeight(int height) {
   handler_->UpdateMaxDialogHeight(height);
 }
 
+void MediaRouterUI::PlayRoute() {
+  if (route_controller_)
+    route_controller_->Play();
+}
+
+void MediaRouterUI::PauseRoute() {
+  if (route_controller_)
+    route_controller_->Pause();
+}
+
+void MediaRouterUI::SeekRoute(uint32_t time) {
+  if (route_controller_)
+    route_controller_->Seek(time);
+}
+
+void MediaRouterUI::SetRouteVolume(float volume) {
+  if (route_controller_)
+    route_controller_->SetVolume(volume);
+}
+
+void MediaRouterUI::SetRouteMute(bool mute) {
+  if (route_controller_)
+    route_controller_->SetMute(mute);
+}
+
+void MediaRouterUI::OnUIDetailsViewOpened(MediaRoute::Id route_id) {
+  if (!IsValidRouteId(route_id))
+    return;
+  selected_route_ = base::Optional<MediaRoute::Id>(route_id);
+  route_controller_ = router_->GetControllerForRoute(route_id);
+  route_status_observer_ =
+      base::MakeUnique<UIMediaRouteStatusObserver>(handler_);
+  route_controller_->AddObserver(route_status_observer_.get());
+}
+
+void MediaRouterUI::OnUIDetailsViewClosed() {
+  selected_route_.reset();
+  if (route_controller_)
+    route_controller_->RemoveObserver(route_status_observer_.get());
+  route_controller_ = nullptr;
+  route_status_observer_.reset();
+}
+
+bool MediaRouterUI::IsValidRouteId(const MediaRoute::Id& route_id) const {
+  return std::find_if(routes_.begin(), routes_.end(),
+                      [&route_id](const MediaRoute& route) {
+                        return route.media_route_id() == route_id;
+                      }) != routes_.end();
+}
+
 std::string MediaRouterUI::GetSerializedInitiatorOrigin() const {
   url::Origin origin = initiator_
                            ? url::Origin(initiator_->GetLastCommittedURL())