DO NOT MERGE) ExifInterface: Make saveAttributes throw an exception before change

ExifInterface object can be created with a unsupported file format.
If saveAttribute is called with an unsupported file format, ExifInterface
makes the file corrupted. This CL prevents those cases by throwing
an exception before making any change on the file.

1d042b8095ce65a5b23aff8b60c46c2eb0289ef6
CYNGNOS-3303
Bug: 30936376
Change-Id: I915f56b00ec9422b53591ac5534e070a1d6798e6
(cherry picked from commit 2ee53c82)