Make reloading color options thread safe am: 4c74f6f9fe am: 998c21eb65

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/18030545

Change-Id: I82efbd35a0165ddbb0066ad109167b944a92b636
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>