Track attribute ranges, parse additional times.

An upcoming privacy feature is interesting in knowing the exact
offset and length of specific Exif tags, similar to how the thumbnail
range is already being returned.  Detect the case where we've modified
the underlying file, meaning ranges are no longer valid.

Add constructor to accept best-practices File object.  Add method to
ask if a given tag has been defined.  Add methods to parse additional
timestamp values.

Bug: 115377970, 111892141
Test: atest android.media.cts.ExifInterfaceTest
Change-Id: Iac35bb65ff7b3605d6c32ec3ca3d29b17e65cff8