This seems to indicate a strange behavior in Android: users selecting a suggestion without a Start(on_focus) event being called.

https://codereview.chromium.org/2689803002/
Adds additional logging to look for this case explicitly.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6b89f92fabae32da4caae8f1b0c387888ade9496

commit 6b89f92fabae32da4caae8f1b0c387888ade9496
Author: mattreynolds <mattreynolds@chromium.org>
Date: Thu Feb 23 20:53:29 2017

Improve nearby URL count metrics for Physical Web omnibox provider

The nearby_url_count_ field was not initialized correctly in the query
suggest case. This CL ensures that the field is always set to the
number of metadata items returned by the Physical Web data source.

A new histogram is added to record the number of nearby URLs when the
omnibox is focused. Another histogram is added to detect how frequently
this corner case occurs.

BUG= 691059 

Review-Url: https://codereview.chromium.org/2689803002
Cr-Commit-Position: refs/heads/master@{#452620}

[modify] https://crrev.com/6b89f92fabae32da4caae8f1b0c387888ade9496/components/omnibox/browser/physical_web_provider.cc
[modify] https://crrev.com/6b89f92fabae32da4caae8f1b0c387888ade9496/components/omnibox/browser/physical_web_provider.h
[modify] https://crrev.com/6b89f92fabae32da4caae8f1b0c387888ade9496/components/omnibox/browser/physical_web_provider_unittest.cc
[modify] https://crrev.com/6b89f92fabae32da4caae8f1b0c387888ade9496/tools/metrics/histograms/histograms.xml

FYI, the counts for all these histograms now look sane in the Android dev channel.  [link omitted on public bug]

Close as fixed?

Yep, the results in NearbyURLCount.AtFocus and NearbyURLCount.AtMatchCreation seem reasonable.  Marking this as fixed.

I notice that Omnibox.PhysicalWebProvider.SuggestionUsedWithoutOmniboxFocus records that the omnibox was used without focus ~1% of the time on Android. Since we still don't know what is causing that, I've filed a new bug so we can continue to track it:

https://bugs.chromium.org/p/chromium/issues/detail?id=699706