This is the cherry pick merge for the M73 branch which was approved here:

[Autofill Assistant] Add a histogram for drop outs.

This patch introduces a histogram to track how AA is closed or fails.
It only includes the drop out part with an initial generic "Autostart"
event for "no drop out". Another histogram for different flavors to start
AA will follow. Some of these bucket names will be refined later.

Bug: 806868
Change-Id: If97a7dde70e2be61424838c426cf076a0241e885
Commit-Queue: Mathias Carlen <>
Reviewed-by: Brian White <>
Reviewed-by: Stephane Zermatten <>
Cr-Original-Commit-Position: refs/heads/master@{#626536}(cherry picked from commit 217b627b04a4738b942fbd4bdc8d5a39b225ac1d)
Reviewed-by: Mathias Carlen <>
Cr-Commit-Position: refs/branch-heads/3683@{#107}
Cr-Branched-From: e51029943e0a38dd794b73caaf6373d5496ae783-refs/heads/master@{#625896}
21 files changed