Create profiles folders

Current profiles (the ones which have not been used for
compilation) are stored in /data/misc/profiles/cur/0/pkgname/.

Reference profiles (the merged of all user profiles, used for
compilation) are stored in /data/misc/profiles/ref/pkgname/.

Add a method to get the shared app gid from an uid or appid.

Bug: 26719109
Bug: 26563023
Change-Id: I89601d7dbeb3041df882c141a9127dac200a645e