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 checkapi
Bug: 299366704
Change-Id: Idba307148fd9afa87bfb7e0c89e00d9bd97ec204