Sending autofill types for username fields in sign-in forms for improving username detection.

components/autofill/core/browser/autofill_manager.cc

 // 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.
 
 #include "components/autofill/core/browser/autofill_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1989 matching lines @@
 // static
 void AutofillManager::DeterminePossibleFieldTypesForUpload(
     const std::vector<AutofillProfile>& profiles,
     const std::vector<CreditCard>& credit_cards,
     const std::string& app_locale,
     FormStructure* submitted_form) {
   // For each field in the |submitted_form|, extract the value.  Then for each
   // profile or credit card, identify any stored types that match the value.
   for (size_t i = 0; i < submitted_form->field_count(); ++i) {
     AutofillField* field = submitted_form->field(i);
+    if (!field->possible_types().empty()) {
+      // If this is an upload for password form submission, Password Manager
+      // could already set types for some fields.

[Roger McFarlane (Chromium), 2017/04/04 19:09:42]

The goal of this function is to include all of the data matches; I'm not sure I
agree with the early continue. Why do we want to exclude the other potential
field types?

[dvadym, 2017/04/05 13:28:28]

Good point. I thought, when I was writing this code, that we are interested only
in password types. But with your comment to password_form_manager, I've realized
that sometimes we could save some other type of information, that's obviously
incorrect, and adding all votes we can figure out when we fail. 
I've updated code, for adding new types in possible_types

+      continue;
+    }
     ServerFieldTypeSet matching_types;
 
     base::string16 value;
     base::TrimWhitespace(field->value, base::TRIM_ALL, &value);
 
     for (const AutofillProfile& profile : profiles)
       profile.GetMatchingTypes(value, app_locale, &matching_types);
     for (const CreditCard& card : credit_cards)
       card.GetMatchingTypes(value, app_locale, &matching_types);
 
@@ skipping 178 matching lines @@
 }
 #endif  // ENABLE_FORM_DEBUG_DUMP
 
 void AutofillManager::LogCardUploadDecisionUkm(
     AutofillMetrics::CardUploadDecisionMetric upload_decision) {
   AutofillMetrics::LogCardUploadDecisionUkm(
       client_->GetUkmService(), pending_upload_request_url_, upload_decision);
 }
 
 }  // namespace autofill