[Autofill] Add a new metric for upstream.

components/autofill/core/browser/autofill_metrics.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_METRICS_H_
 #define COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_METRICS_H_
 
 #include <stddef.h>
 #include <string>
 
@@ skipping 344 matching lines @@
     // to fill.
     FORM_EVENT_SERVER_SUGGESTION_FILLED,
     // A masked server card suggestion was used to fill the form.
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_FILLED,
     // A suggestion was used to fill the form. The origin type (local or server
     // or masked server card) of the first selected within a page load will
     // determine which of the following two will be fired.
     FORM_EVENT_LOCAL_SUGGESTION_FILLED_ONCE,
     FORM_EVENT_SERVER_SUGGESTION_FILLED_ONCE,
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_FILLED_ONCE,
+    // A dropdown with suggestions was shown and a form was submitted after that
+    FORM_EVENT_SUGGESTION_SHOWN_SUBMITTED_ONCE,

[Jared Saul, 2016/12/15 22:20:59]

Looks like this is a duplicate now; remove?

[Shanfeng, 2016/12/15 23:28:12]

Done.

     // A form was submitted. Depending on the user filling a local, server,
     // masked server card or no suggestion one of the following will be
     // triggered. Only one of the following four will be triggered per page
     // load.
     FORM_EVENT_NO_SUGGESTION_SUBMITTED_ONCE,
     FORM_EVENT_LOCAL_SUGGESTION_SUBMITTED_ONCE,
     FORM_EVENT_SERVER_SUGGESTION_SUBMITTED_ONCE,
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_SUBMITTED_ONCE,
     // A masked server card suggestion was selected to fill the form.
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_SELECTED,
     // Same as above but only triggered once per page load.
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_SELECTED_ONCE,
+    // A dropdown with suggestions was shown and a form was submitted after that

[Jared Saul, 2016/12/15 22:20:59]

nit: s/that/that.
(for consistency; all the others end in a period)

[Shanfeng, 2016/12/15 23:28:12]

Done.

+    FORM_EVENT_SUGGESTION_SHOWN_SUBMITTED_ONCE,
+    // A dropdown with suggestions was shown and a form is about to be
+    // submitted. If the submission is not interrupted by JavaScript, the "form
+    // submitted" event above will also be logged.
+    FORM_EVENT_SUGGESTION_SHOWN_WILL_SUBMIT_ONCE,
     // An autofillable form is about to be submitted. If the submission is not
     // interrupted by JavaScript, the "form submitted" events above will also be
     // logged. Depending on the user filling a local, server, masked server card
     // or no suggestion one of the following will be triggered, at most once per
     // page load.
     FORM_EVENT_NO_SUGGESTION_WILL_SUBMIT_ONCE,
     FORM_EVENT_LOCAL_SUGGESTION_WILL_SUBMIT_ONCE,
     FORM_EVENT_SERVER_SUGGESTION_WILL_SUBMIT_ONCE,
     FORM_EVENT_MASKED_SERVER_CARD_SUGGESTION_WILL_SUBMIT_ONCE,
 
@@ skipping 320 matching lines @@
     FormFieldData last_polled_field_;
   };
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(AutofillMetrics);
 };
 
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_CORE_BROWSER_AUTOFILL_METRICS_H_