Redact location Exif tags when no permission.

When the caller doesn't hold the ACCESS_MEDIA_LOCATION permission,
any location Exif tags should be redacted for privacy reasons.  We
still allow unredacted raw file access if the media is owned by the
calling app, since they should be able to see data they contributed.

Certain backup apps really want to see the original contents without
any redaction, so provide them a setRequireOriginal() API so they
get a strong exception whenever the original bits can't be provided.

Add the ability to open a redacted file for read/write access by
stopping redaction for any ranges that have been overwritten with
new data, along with tests to verify this behavior.

Extend "content" tool to bind null values.

Bug: 111892141
Test: atest android.os.RedactingFileDescriptorTest
Test: atest cts/tests/tests/provider/src/android/provider/cts/MediaStore*
Change-Id: I47b220036a712d9d49547196b90e031b10760f84