Merge "Sharesheet: action bar is independent of WP tabs, should always launch...

Merge "Sharesheet: action bar is independent of WP tabs, should always launch as primary user." into sc-dev am: 9197f7b2 am: b566f49a am: bfe51607

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15363687

Change-Id: Icf16e4c0900407d469cbf24808c9973d82f2972f