Introduce CdmContext interface.

media/base/media_keys.h

Index: media/base/media_keys.h
diff --git a/media/base/media_keys.h b/media/base/media_keys.h
index 022f6bcce29078d5ab3142dc0eaa9074b900906a..0f42a1420104d093733f9bfbfd203c306fa7825e 100644
--- a/media/base/media_keys.h
+++ b/media/base/media_keys.h
@@ -11,6 +11,7 @@
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
+#include "media/base/cdm_context.h"
 #include "media/base/media_export.h"
 #include "url/gurl.h"
 
@@ -34,7 +35,7 @@ typedef CdmPromiseTemplate<KeyIdsVector> KeyIdsPromise;
 //
 // All key operations are called on the renderer thread. Therefore, these calls
 // should be fast and nonblocking; key events should be fired asynchronously.
-class MEDIA_EXPORT MediaKeys {
+class MEDIA_EXPORT MediaKeys : public CdmContext{
  public:
   // Reported to UMA, so never reuse a value!
   // Must be kept in sync with blink::WebMediaPlayerClient::MediaKeyErrorCode
@@ -72,12 +73,9 @@ class MEDIA_EXPORT MediaKeys {
   };
 
   static const uint32 kInvalidSessionId = 0;
-#if defined(ENABLE_BROWSER_CDMS)
-  static const int kInvalidCdmId = 0;
-#endif
 
   MediaKeys();
-  virtual ~MediaKeys();
+  ~MediaKeys() override;
 
   // Provides a server certificate to be used to encrypt messages to the
   // license server.
@@ -121,16 +119,8 @@ class MEDIA_EXPORT MediaKeys {
   virtual void GetUsableKeyIds(const std::string& web_session_id,
                                scoped_ptr<KeyIdsPromise> promise) = 0;
 
-  // Gets the Decryptor object associated with the MediaKeys. Returns NULL if
-  // no Decryptor object is associated. The returned object is only guaranteed
-  // to be valid during the MediaKeys' lifetime.
-  virtual Decryptor* GetDecryptor();
-
-#if defined(ENABLE_BROWSER_CDMS)
-  // Returns the CDM ID associated with |this|. May be kInvalidCdmId if no CDM
-  // ID is associated.
-  virtual int GetCdmId() const = 0;
-#endif
+  // CdmContext implementation
+  Decryptor* GetDecryptor() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MediaKeys);