No need to pass digest of AndroidManifest.xml around.

When an APK is being installed, the full path to the file is
occasionally passed between processes. To detect changes to the file
during these handovers, the digest of the AndroidManifest.xml entry
could be passed around as well.

This security feature is no longer used and is no longer needed. APKs
should be installed using the modern Package Installer API
(android.content.pm.PackageInstaller).

Bug: 24542768
Change-Id: I2762634c85448e7adcd47ffc9a5294c021e127bd