Fix wrong use if "!UserHandle.isApp()"

Turned out !UserHandle.isApp() doesn't mean "is system" because of isolated UIDs.

Bug: 72174012
Test: atest $ANDROID_BUILD_TOP/frameworks/base/services/tests/servicestests/src/com/android/server/ForceAppStandbyTrackerTest.java
Change-Id: Ibf6175d550ecc74677877c74db2473bf3f30132d
4 files changed