Revert "Revert "ActivityManager: memorize for performance""

This reverts commit 3133ed873aa48f9b06206d891e4a822cccb47944.
Revert "Revert "IntentService: Fix to run with a lower priority flag.""

This reverts commit 79dbf564287571e5bb8943ba49ec91ff4eb2592e.
Revert "Revert "ActivityManagerService: stay away from zombie content providers""

This reverts commit 3a4ea3a2168c2e71fcc316b5ad951da5d6c9ad00.
Revert "Revert "DefaultContainerService: implement additional methods""

This reverts commit 113ba7d286699bdd0b57363bc85fde37f76c1e8d.
Revert "Revert "am: Allow more hidden apps on devices with lots of RAM""

This reverts commit 81d0e6fb3c65becc82c0fa37ea69b7be3e8a9276.