Also:
1. Add AssetManager method for finding non-system locales: This is
used in per-app locale negotiation. (Normally,
AssetManager#getLocales() returns both system and non-system
locales.)
2. Match pseudolocales correctly in locale negotiation.
Bug: 25800576
Bug: 26236938
Change-Id: I116caf3a91c290deb4ad68b291c65b7035b18dd4