Add methods to Parcel for bool and char and byte

We lift these to int, but handling the details of that here will be better
than having AIDL generate casting code all the time.

Test: unit tests pass
Bug: 24981507
Signed-off-by: Casey Dahlin <sadmac@google.com>

(cherry picked from commit d6848f52)

Change-Id: I471586463360c37e837b1b8f862da3b5e17f905d