[automerger skipped] Clean up staged session data on validation failure am: 58432ac6 -s ours am: eac7e1ee

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/13112799

Change-Id: If6ae8f75601e0257f26cc92a2af56ec69a4ad6c8