[Media Router] Remove the extension ID getter from MRMojoImpl

This CL removes the media_route_provider_extension_id() getter from
MediaRouterMojoImpl, which was previously being accessed by static-casting
MediaRouter into MediaRouterMojoImpl. The getter in EventPageRequestManager is
now used.

It seems that we cannot simply hard-code the ID, since it's different between
dev and release builds of the component extension.

BUG=597778
BUG=727993

Review-Url: https://codereview.chromium.org/2970273002
Cr-Commit-Position: refs/heads/master@{#485439}

chrome/browser/media/router/mojo/media_router_mojo_impl.cc

@@ -222,11 +222,6 @@ void MediaRouterMojoImpl::OnRoutesUpdated(
   RemoveInvalidRouteControllers(routes);
 }
 
-const std::string& MediaRouterMojoImpl::media_route_provider_extension_id()
-    const {
-  return event_page_request_manager_->media_route_provider_extension_id();
-}
-
 void MediaRouterMojoImpl::RouteResponseReceived(
     const std::string& presentation_id,
     bool is_incognito,

chrome/browser/media/router/mojo/media_router_mojo_impl.h

@@ -115,9 +115,6 @@ class MediaRouterMojoImpl : public MediaRouterBase,
   scoped_refptr<MediaRouteController> GetRouteController(
       const MediaRoute::Id& route_id) override;
 
-  // TODO(crbug.com/597778): Remove this getter.
-  const std::string& media_route_provider_extension_id() const;
-
   void set_instance_id_for_test(const std::string& instance_id) {
     instance_id_ = instance_id;
   }
@@ -218,7 +215,7 @@ class MediaRouterMojoImpl : public MediaRouterBase,
 
   // Binds |this| to a Mojo interface request, so that clients can acquire a
   // handle to a MediaRouterMojoImpl instance via the Mojo service connector.
-  // Stores the ID of |extension| in |media_route_provider_extension_id_|.
+  // Passes the extension's ID to the event page request manager.
   void BindToMojoRequest(
       mojo::InterfaceRequest<mojom::MediaRouter> request,
       const extensions::Extension& extension);

chrome/browser/ui/toolbar/media_router_contextual_menu.cc

@@ -9,6 +9,8 @@
 #include "base/logging.h"
 #include "base/metrics/user_metrics.h"
 #include "chrome/app/chrome_command_ids.h"
+#include "chrome/browser/media/router/event_page_request_manager.h"
+#include "chrome/browser/media/router/event_page_request_manager_factory.h"
 #include "chrome/browser/media/router/media_router_factory.h"
 #include "chrome/browser/media/router/mojo/media_router_mojo_impl.h"
 #include "chrome/browser/profiles/profile.h"
@@ -182,17 +184,15 @@ void MediaRouterContextualMenu::ExecuteCommand(int command_id,
 void MediaRouterContextualMenu::ReportIssue() {
   // Opens feedback page loaded from the media router extension.
   // This is temporary until feedback UI is redesigned.
-  // TODO(crbug.com/597778): remove reference to MediaRouterMojoImpl
-  media_router::MediaRouterMojoImpl* media_router =
-      static_cast<media_router::MediaRouterMojoImpl*>(
-          media_router::MediaRouterFactory::GetApiForBrowserContext(
-              static_cast<content::BrowserContext*>(browser_->profile())));
-  if (media_router->media_route_provider_extension_id().empty())
+  media_router::EventPageRequestManager* request_manager =
+      media_router::EventPageRequestManagerFactory::GetApiForBrowserContext(
+          browser_->profile());
+  if (request_manager->media_route_provider_extension_id().empty())
     return;
-  std::string feedback_url(extensions::kExtensionScheme +
-                           std::string(url::kStandardSchemeSeparator) +
-                           media_router->media_route_provider_extension_id() +
-                           "/feedback.html");
+  std::string feedback_url(
+      extensions::kExtensionScheme +
+      std::string(url::kStandardSchemeSeparator) +
+      request_manager->media_route_provider_extension_id() + "/feedback.html");
   chrome::ShowSingletonTab(browser_, GURL(feedback_url));
 }
 

chrome/browser/ui/webui/cast/cast_ui.cc

@@ -4,8 +4,8 @@
 
 #include "chrome/browser/ui/webui/cast/cast_ui.h"
 
-#include "chrome/browser/media/router/media_router_factory.h"
-#include "chrome/browser/media/router/mojo/media_router_mojo_impl.h"
+#include "chrome/browser/media/router/event_page_request_manager.h"
+#include "chrome/browser/media/router/event_page_request_manager_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/browser_resources.h"
@@ -16,11 +16,11 @@
 CastUI::CastUI(content::WebUI* web_ui)
     : content::WebUIController(web_ui) {
   // Retrieve the ID of the component extension.
-  // TODO(crbug.com/597778): remove reference to MediaRouterMojoImpl.
-  auto* router = static_cast<media_router::MediaRouterMojoImpl*>(
-      media_router::MediaRouterFactory::GetApiForBrowserContext(
-          web_ui->GetWebContents()->GetBrowserContext()));
-  std::string extension_id = router->media_route_provider_extension_id();
+  auto* event_page_request_manager =
+      media_router::EventPageRequestManagerFactory::GetApiForBrowserContext(
+          web_ui->GetWebContents()->GetBrowserContext());
+  std::string extension_id =
+      event_page_request_manager->media_route_provider_extension_id();
 
   // Set up the chrome://cast data source and add required resources.
   content::WebUIDataSource* html_source =

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

@@ -18,6 +18,8 @@
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/media/router/create_presentation_connection_request.h"
+#include "chrome/browser/media/router/event_page_request_manager.h"
+#include "chrome/browser/media/router/event_page_request_manager_factory.h"
 #include "chrome/browser/media/router/issues_observer.h"
 #include "chrome/browser/media/router/media_router.h"
 #include "chrome/browser/media/router/media_router_factory.h"
@@ -230,9 +232,11 @@ MediaRouterUI::MediaRouterUI(content::WebUI* web_ui)
 
   content::WebContents* wc = web_ui->GetWebContents();
   DCHECK(wc);
+  content::BrowserContext* context = wc->GetBrowserContext();
 
-  router_ =
-      MediaRouterFactory::GetApiForBrowserContext(wc->GetBrowserContext());
+  router_ = MediaRouterFactory::GetApiForBrowserContext(context);
+  event_page_request_manager_ =
+      EventPageRequestManagerFactory::GetApiForBrowserContext(context);
 
   // Allows UI to load extensionview.
   // TODO(haibinlu): limit object-src to current extension once crbug/514866
@@ -858,9 +862,7 @@ const std::set<MediaCastMode>& MediaRouterUI::cast_modes() const {
 }
 
 const std::string& MediaRouterUI::GetRouteProviderExtensionId() const {
-  // TODO(crbug.com/597778): remove reference to MediaRouterMojoImpl
-  return static_cast<MediaRouterMojoImpl*>(router_)
-      ->media_route_provider_extension_id();
+  return event_page_request_manager_->media_route_provider_extension_id();
 }
 
 void MediaRouterUI::SetUIInitializationTimer(const base::Time& start_time) {

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

@@ -44,6 +44,7 @@ class Browser;
 namespace media_router {
 
 class CreatePresentationConnectionRequest;
+class EventPageRequestManager;
 class IssuesObserver;
 class MediaRoute;
 class MediaRouter;
@@ -414,6 +415,9 @@ class MediaRouterUI
   // Pointer to the MediaRouter for this instance's BrowserContext.
   MediaRouter* router_;
 
+  // Request manager for the Media Router component extension.
+  const EventPageRequestManager* event_page_request_manager_;
+
   // The start time for UI initialization metrics timer. When a dialog has been
   // been painted and initialized with initial data, this should be cleared.
   base::Time start_time_;