Changing IntentSender to become a listener.

Listener is more secure as nobody can send a broadcast with invalid
digests.

Bug: 160605420
Test: atest PackageManagerShellCommandTest PackageManagerShellCommandIncrementalTest IncrementalServiceTest PackageManagerServiceTest ChecksumsTest
Change-Id: I5f6ec3f0fa975d274d456d11d57be61d0b245e80
9 files changed