Merge "Only update default home when the preferred home activity is modified."...

Merge "Only update default home when the preferred home activity is modified." into sc-dev am: bfdcaaf2 am: 17d78b32

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14314665

Change-Id: I21cfc392c67ca963c4f393af881980971016f71d