Merge "Fix potential crash in SearchFragment#dismiss()." into rvc-dev am: 51f5c340 am: 7d8d7a16 am: 5dd4fafa am: 6c98fb48 am: 9759f12e

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/DocumentsUI/+/12042990

Change-Id: Iadfbf004e7ebf133db5536a9a23d703acd13871c