Revert "Do not dexpreopt system server jars from updatable modules."

This reverts commit 61c325eb.

Reason for revert: broken build git_master/cf_x86_phone-userdebug_coverage (likely caused by these changes).

Exempt-From-Owner-Approval: revert.

Change-Id: I88ddd3af3a6c4ffdaa1fbb881d965356c5c75ad3