Fix MediaRouter bugs
Fix MediaRouter bugs

Fix a bug where a newly added group had no supported types at the time
of callback dispatch, meaning that no registered callbacks would be
invoked.

Fix a bug where subscribed type flags were not updated properly when
re-adding a callback for new types.

Change-Id: I7d9f11b363ebdca692786cec1d432600946e5721

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base