Fix prefix-correlation weakness in filenames encryption by switching to
AES-256-HCTR2. Enabling HCTR2 fixes a longstanding known weakness in
filenames encryption.
Also enable HCTR2 for adoptable storage. Pixel phones don't have an SD
card slot. So they can only have adoptable storage through the "Virtual
SD Card", which is for testing only.
Bug: 265046004
Test: Equivalent changes were tested on P21 since I don't have a P23.
Will be tested with storage-qa.
Change-Id: I0666eb07c4b93b1bab4da41e3b4f5019ac38c213