Fill AVRCP queue Metadata with MediaController Metadata

When retrieving the Media metadata using
MediaSession#QueueItem, we can loose some information such
as media duration. To prevent this, we need to add to the
the stored QueueItem metadata the data retrieved from the
MediaController for the current playing media.

Now that the other media metadata is available for current
media QueueItem, we also need to update the equals overload
of the Metadata class to reflect these changes.

Modified and added tests accordingly.

Bug: 235637427
Tag: #feature
Test: MediaPlayerWrapperTest
Change-Id: Iefc7de8767ffab8fa14f9cf1f120ef4804791cd1