Add additional overriding methods to signature files

This change adds overriding methods that are essential to compile the
stubs generated from the signature files.

More information and the background for this change is available at go/add-overriding-one-pager.

Test: m checkbuild --build-from-text-stub
Bug: 299366704
(cherry picked from https://android-review.googlesource.com/q/commit:6131efddce0957c0240b9bf4331e021540a3ac4a)
Merged-In: I301ec87464be4fa89380b2ccb8b8b305676ec67f
Change-Id: I301ec87464be4fa89380b2ccb8b8b305676ec67f
2 files changed