[automerger skipped] Merge "Add documentation for BlobStore service." am: 8aebd244de am: 51dcd40ff3 am: c22baf983c am: 2a920b28e6 am: 06cc197cba -s ours

am skip reason: Merged-In Id55d593856d6194cd620211cc3bca981e572d15a with SHA-1 c93b97c26b is already in history

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1880596

Change-Id: I5bb94fb31b541faaaf16299ac1e52f403610e4ce