Set pm.BackgroundDexOptService as the source of true

Set pm.BackgroundDexOptService as the source of true

The real dexopt maintainance job is
com.android.server.pm.BackgroundDexOptService, and not
com.android.server.BackgroundDexOptJobService

Partial revert of commit 096d304ae3d85c1bfcda1a1d9cd4eb13d0815500.

Test: manual inspection
Bug: 36140426

(partial cherry picked from commit
91d40f1baa2eeed2aa68d2492e20650d5e71dab5)

Merged-In: I983ac91117f107282095fa7eefdbce08e0dcfce3
Change-Id: I983ac91117f107282095fa7eefdbce08e0dcfce3

# Conflicts:
#	core/res/AndroidManifest.xml
#
services/core/java/com/android/server/pm/PackageManagerService.java
#	services/java/com/android/server/SystemServer.java