Remove INSTALLED_USERS extra from ACTION_PACKAGE_ENABLE_ROLLBACK.

This changes RollbackManagerServiceImpl to use the list of installed users
that is passed in to snapshotAndRestoreUserData for the purpose of snapshotting.

With this change, it is no longer necessary for the list of installed users to be
added as an extra to the ENABLE_ROLLBACK intent, so that extra
(EXTRA_ENABLE_ROLLBACK_INSTALLED_USERS) is removed.

Bug: 139181444
Test: atest RollbackTest
Test: atest AppDataRollbackHelperTest
Exempt-From-Owner-Approval: Already approved in
https://googleplex-android-review.git.corp.google.com/c/platform/frameworks/base/+/9168506

Change-Id: Iff42f4e5b2d02d1124d64a5fedc659a41cddd5fc
Merged-In: Iffd63977a7498e3cba20d2039af623c921d38f57