Improve notifying TimedText by reducing marshall/unmarshalling.

o Removes mParcel from TimedText class.
o Converts native parcel into java parcel object directly without
copying to an intermediate byte array.
o JNIMediaPlayerListener::notify checks for Java exceptions, logs them,
and clears the exception state.

related-to-bug: 6405934

Change-Id: I8b82d3cd5b9b3ef8cad27e805202a0e445a88a45