[automerge] StorageManagerService: don't ignore failures to prepare user storage 2p: 567e7a0476

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17416116

Bug: 164488924
Bug: 224585613
Change-Id: I2144b6e848dffc9a8b3af9983e16644d2d5b5785
Merged-In: I9a38ab5cca1ae9c9ebff81fca04615fd83ebe4b2