Merge "Crash happens if back button is pressed during "Format as Portable""...

Merge "Crash happens if back button is pressed during "Format as Portable"" am: 671fa153 am: 6945e70c am: c80890c7 am: 85768c59

Original change: https://android-review.googlesource.com/c/platform/packages/apps/Settings/+/2147940



Change-Id: I2ca9ead163513a72e73d10af44df5112c05b61b6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>