Update WebContentDecryptionModuleSessionImpl to the latest EME spec.

content/renderer/media/webcontentdecryptionmodulesession_impl.h

Index: content/renderer/media/webcontentdecryptionmodulesession_impl.h
diff --git a/content/renderer/media/webcontentdecryptionmodulesession_impl.h b/content/renderer/media/webcontentdecryptionmodulesession_impl.h
index 12c4fc31fa6306e1713ea10d65e6779a1359b0c5..c614ee3a978505a966df476e7c1a58b9c2239e84 100644
--- a/content/renderer/media/webcontentdecryptionmodulesession_impl.h
+++ b/content/renderer/media/webcontentdecryptionmodulesession_impl.h
@@ -34,10 +34,17 @@ class WebContentDecryptionModuleSessionImpl
 
   // blink::WebContentDecryptionModuleSession implementation.
   virtual blink::WebString sessionId() const;
+  virtual void initializeNewSession(const blink::WebString& mime_type,
+                                    const uint8* init_data,
+                                    size_t init_data_length);
+  virtual void update(const uint8* response, size_t response_length);
+  virtual void release();
+
+  // TODO(xhwang): Drop generateKeyRequest() and close() after blink side is
+  // updated.
   virtual void generateKeyRequest(const blink::WebString& mime_type,
                                   const uint8* init_data,
                                   size_t init_data_length);
-  virtual void update(const uint8* response, size_t response_length);
   virtual void close();
 
   // Callbacks.