Merge "Postpone headless app caching to after boot." into rvc-dev am: fd910278 am: 4d704628 am: bf85c836

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11973241

Change-Id: Ia7084170facff5fdc4a4ff430888f53aa2e046e6