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

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

Change-Id: Icf2ee1bb9f5995c9487993bf7d5e3be7c0a02c9f