Omnibox - Zero Suggest - Log When/Whether Contextual Search is Possible

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index cb82893278aa4b851c63fcc19b4c681c08e78edb..6c582f31628d9e494d28bf43a08cd118529692cf 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -43666,6 +43666,57 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Omnibox.ZeroSuggest.Eligible.OnFocus"
+    enum="ZeroSuggestEligibleOnFocus">
+  <owner>mpearson@chromium.org</owner>
+  <summary>
+    Whether the user has settings configured so that the current page URL can be
+    sent to the suggest server to request contextual suggestions.  For example,
+    this is only supported for users who have Google as their default search
+    engine (unmodified version of Google), have search suggest enabled, are
+    signed-in and syncing without a custom passphrase, and don't have an
+    incognito window open.  There are other criteria too.  Recorded on focus in
+    the omnibox if there is default search provider and we've constructed a
+    suggest URL.
+
+    Some additional guidelines: if an incognito window is open, all focus events
+    will go into the &quot;generally ineligible&quot; bucket. Likewise, if the
+    current page is a search results page, we don't allow contextual suggestions
+    either so focus events on those pages go in the &quot;generally
+    ineligible&quot; bucket.  The difference between &quot;eligible&quot; and
+    &quot;generally eligible but not this time&quot; depends only the properties
+    of the current URL.
+
+    Recorded regardless of whether contextual or non-contextual zero suggest is
+    currently enabled on the user's platform.  However, if zero suggest (in all
+    forms) is entirely disabled, the user will be perpetually ineligible.
+  </summary>
+</histogram>
+
+<histogram name="Omnibox.ZeroSuggest.Eligible.OnProfileOpen"
+    enum="BooleanSupported">
+  <owner>mpearson@chromium.org</owner>
+  <summary>
+    Whether the user has settings configured so that the current page URL could
+    be sent to the suggest server to request contextual suggestions.  For
+    example, this is only supported for users who have Google as their default
+    search engine (unmodified version of Google), have search suggest enabled,
+    and are signed-in and syncing without a custom passphrase.  There are other
+    criteria too.  Recorded on profile open.
+
+    Some additional guidelines: unlike Omnibox.ZeroSuggest.Eligible.OnFocus,
+    because this is recorded on profile open, users cannot be declared
+    ineligible because they have an incognito window open (it's impossible to
+    have an incognito window open for a given profile at the time of profile
+    open) and also cannot be declared ineligible because the user is viewing a
+    search results page.  (We test this on-profile-open using an arbitrary URL.)
+
+    Recorded regardless of whether contextual or non-contextual zero suggest is
+    currently enabled on the user's platform.  However, if zero suggest (in all
+    forms) is entirely disabled, the user will be perpetually ineligible.
+  </summary>
+</histogram>
+
 <histogram name="Omnibox.ZeroSuggest.MostVisitedResultsCounterfactual">
   <owner>hfung@chromium.org</owner>
   <summary>
@@ -113233,6 +113284,21 @@ value.
   </int>
 </enum>
 
+<enum name="ZeroSuggestEligibleOnFocus" type="int">

[Ilya Sherman, 2017/03/02 17:42:03]

Wow, you've reached the very tail end of the file!  Good job!  =P

[Mark P, 2017/03/02 21:03:02]

Acknowledged.

I was thinking the same thing too! :-)

+  <int value="0" label="Eligible">
+    URL can be currently sent to the suggest server.
+  </int>
+  <int value="1"
+      label="Generally eligible in current context but particular URL
+             ineligible">
+    URL cannot be sent to the suggest server but another URL would be eligible
+    at this time.
+  </int>
+  <int value="2" label="Generally ineligible in current context">
+    No URL can be send to the suggest server at this time.
+  </int>
+</enum>
+
 </enums>
 
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