Merge "Add proto tombstones to Dropbox." am: 3361ca6c56 am: 093e8d266a am: a1b7331722

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1590892

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I490ba33c58b47c29f0c828bd0f1bcbe7f1eb24c0