media: Make MediaKeys ref-counted.

media/mojo/services/mojo_cdm_service.h

Index: media/mojo/services/mojo_cdm_service.h
diff --git a/media/mojo/services/mojo_cdm_service.h b/media/mojo/services/mojo_cdm_service.h
index 0f974da1a234ae8581a0acf47fceed9a22d06a0d..c669a74b73b9fd3d4f14da7f374ae8b5164c7e6b 100644
--- a/media/mojo/services/mojo_cdm_service.h
+++ b/media/mojo/services/mojo_cdm_service.h
@@ -7,6 +7,7 @@
 
 #include "base/callback.h"
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "media/base/media_keys.h"
@@ -76,7 +77,7 @@ class MojoCdmService : public interfaces::ContentDecryptionModule {
  private:
   // Callback for CdmFactory::Create().
   void OnCdmCreated(scoped_ptr<MojoCdmPromise<int>> promise,
-                    scoped_ptr<MediaKeys> cdm,
+                    const scoped_refptr<MediaKeys>& cdm,
                     const std::string& error_message);
 
   // Callbacks for firing session events.
@@ -105,7 +106,7 @@ class MojoCdmService : public interfaces::ContentDecryptionModule {
 
   mojo::ServiceProvider* service_provider_;
   CdmFactory* cdm_factory_;
-  scoped_ptr<MediaKeys> cdm_;
+  scoped_refptr<MediaKeys> cdm_;
 
   // Set to a valid CDM ID if the |cdm_| is successfully created.
   int cdm_id_;