Gracefully handle apps passing in invalid paths.

We've seen apps try crossing the streams between volumes; we still
don't allow this to happen, but we'll return sane values to
legacy apps that aren't ready to have an exception thrown at them.

Bug: 126104805
Test: atest MediaProviderTests
Test: atest cts/tests/tests/provider/src/android/provider/cts/MediaStore*
Change-Id: I183a607e6027da14eb0844fdbc2cded7c1c3c6fe
2 files changed