Update Framework from Jetpack.

Included changes:
* 4c1b251: Sync AppSearch with google3 update ag/14342999 (8f8b43)
* cdf1913: Add a GenericDocument#toBuilder API.
* 64f80f3: Improve snippeting and matching per API feedback.
* 23dd35c: Move AppSearchEmail out of the prod tree into the test utils.

Bug: 171882200
Bug: 186520196
Bug: 186717514
Test: Presubmit
Change-Id: I9d8e1fb87e6e74c57a38f3a27cdd04a1a3ccf90b