Merge "Null-check mime types in content preview handling" into udc-dev am: a7cdbede1a

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/IntentResolver/+/22861999

Change-Id: I54d4a4b0da11c4dd350348815ef473b99b067025
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>