Merge "Only allow the system server to connect to sync adapters" into qt-dev...

Merge "Only allow the system server to connect to sync adapters" into qt-dev am: 99ccb4e5 am: 822fbf61 am: ea69ad58 am: f15b3c25

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18701369



Change-Id: I1e1671c18a1573e819b76cbfb739d42cadc43aed
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>