Merge "Fix RecyclerViewFastScroller bugs, hide keyboard" into sc-dev am: 6e673c7ed8 am: 877e193ed0

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14931940

Change-Id: I3ffcf993bc1c181495787ab585ce0b543151eb9a