Support transcode via MTP

Add a helper method to open files via MediaProvider ContentResolver.

Note that we are optimizing for the current default transcode option - B
(which is to transcode) and therefore we include the bundle only when we
do not want to transcode.

Test: Manual
Bug: 158466651
Change-Id: I48436ef143feb889b523a9c0e620c2312157ef89
2 files changed