[Media Router] Use DialMediaSinkService in MediaRouterMojoImpl

chrome/browser/media/router/discovery/dial/dial_media_sink_service.h

Index: chrome/browser/media/router/discovery/dial/dial_media_sink_service.h
diff --git a/chrome/browser/media/router/discovery/dial/dial_media_sink_service.h b/chrome/browser/media/router/discovery/dial/dial_media_sink_service.h
index 86f72c5beba6118eb17052fe0f245a9b357fa052..769d1102c3f79ef2ff4674c12eaa5267c1478090 100644
--- a/chrome/browser/media/router/discovery/dial/dial_media_sink_service.h
+++ b/chrome/browser/media/router/discovery/dial/dial_media_sink_service.h
@@ -8,10 +8,12 @@
 #include <memory>
 #include <set>
 
+#include "base/memory/ref_counted.h"
 #include "chrome/browser/media/router/discovery/dial/device_description_service.h"
 #include "chrome/browser/media/router/discovery/dial/dial_registry.h"
 #include "chrome/common/media_router/discovery/media_sink_internal.h"
 #include "chrome/common/media_router/discovery/media_sink_service.h"
+#include "content/public/browser/browser_thread.h"
 
 namespace media_router {
 
@@ -20,34 +22,54 @@ class DialRegistry;
 
 // A service which can be used to start background discovery and resolution of
 // DIAL devices (Smart TVs, Game Consoles, etc.).
-// This class is not thread safe. All methods must be called from the IO thread.
+// This class is thread safe.
 class DialMediaSinkService : public MediaSinkService,
-                             public DialRegistry::Observer {
+                             public DialRegistry::Observer,
+                             public base::RefCountedThreadSafe<
+                                 DialMediaSinkService,
+                                 content::BrowserThread::DeleteOnIOThread> {
  public:
   DialMediaSinkService(const OnSinksDiscoveredCallback& callback,
                        net::URLRequestContextGetter* request_context);
-  ~DialMediaSinkService() override;
-
+  void Stop();

[Kevin M, 2017/05/08 18:22:19]

Add a comment for this method.

[zhaobin, 2017/05/08 20:13:47]

Done.

   // MediaSinkService implementation
   void Start() override;
 
-  void Stop();
-
  protected:
-  virtual DialRegistry* dial_registry();
+  ~DialMediaSinkService() override;
 
   // Returns instance of device description service. Create a new one if none
   // exists.
-  virtual DeviceDescriptionService* GetDescriptionService();
+  DeviceDescriptionService* GetDescriptionService();
+
+  // Does not take ownership of |dial_registry|.
+  void SetDialRegistryForTest(DialRegistry* dial_registry);
+  void SetDescriptionServiceForTest(
+      std::unique_ptr<DeviceDescriptionService> description_service);
+  void SetTimerForTest(std::unique_ptr<base::Timer> timer);
 
  private:
+  friend struct content::BrowserThread::DeleteOnThread<
+      content::BrowserThread::IO>;
+  friend class base::DeleteHelper<DialMediaSinkService>;
   friend class DialMediaSinkServiceTest;
   FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest, TestStart);
-  FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest, TestFetchCompleted);
+  FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest, TestTimer);
+  FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest,
+                           TestFetchCompleted_SameSink);
   FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest, TestIsDifferent);
   FRIEND_TEST_ALL_PREFIXES(DialMediaSinkServiceTest,
                            TestOnDeviceDescriptionAvailable);
 
+  // Start discovery on IO thread.
+  void StartOnIOThread();
+
+  // Stop discovery on IO thread.
+  void StopOnIOThread();
+
+  // Called when |finish_timer_| expires.
+  void OnFetchCompletedOnUIThread();
+
   // api::dial::DialRegistry::Observer implementation
   void OnDialDeviceEvent(const DialRegistry::DeviceList& devices) override;
   void OnDialError(DialRegistry::DialErrorCode type) override;
@@ -62,16 +84,19 @@ class DialMediaSinkService : public MediaSinkService,
   void OnDeviceDescriptionError(const DialDeviceData& device,
                                 const std::string& error_message);
 
-  // Called when |finish_timer_| expires.
+  // Called when |finish_timer_| expires and post task on UI thread.
   void OnFetchCompleted();
 
   // Timer for finishing fetching. Starts in |OnDialDeviceEvent()|, and expires
   // 3 seconds later. If |OnDeviceDescriptionAvailable()| is called after
   // |finish_timer_| expires, |finish_timer_| is restarted.
-  std::unique_ptr<base::OneShotTimer> finish_timer_;
+  std::unique_ptr<base::Timer> finish_timer_;
 
   std::unique_ptr<DeviceDescriptionService> description_service_;
 
+  // Raw pointer to DialRegistry singleton.
+  DialRegistry* dial_registry_;
+
   // Sorted sinks from current round of discovery.
   std::set<MediaSinkInternal> current_sinks_;