Add a function to convert key system into UUID

media/base/android/media_drm_bridge.h

Index: media/base/android/media_drm_bridge.h
diff --git a/media/base/android/media_drm_bridge.h b/media/base/android/media_drm_bridge.h
index 60ecfa14a9cf43443f3dad2ef688f76dcbe8e9ea..291933c3540635673cf0522f535e3ce8aba16e56 100644
--- a/media/base/android/media_drm_bridge.h
+++ b/media/base/android/media_drm_bridge.h
@@ -20,7 +20,7 @@ namespace media {
 class MEDIA_EXPORT MediaDrmBridge : public MediaKeys {
  public:
   // TODO(xhwang): Pass in |key_system|.
-  MediaDrmBridge(int media_keys_id, const std::vector<uint8>& uuid);
+  MediaDrmBridge(int media_keys_id, const std::string& key_system);
   virtual ~MediaDrmBridge();
 
   // Checks whether DRM is available.
@@ -54,6 +54,9 @@ class MEDIA_EXPORT MediaDrmBridge : public MediaKeys {
   // Id of the MediaKeys object.
   int media_keys_id_;
 
+  // UUID of the key system.
+  std::vector<uint8> uuid_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaDrmBridge);
 };