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

components/autofill/core/browser/autofill_manager.cc

Index: components/autofill/core/browser/autofill_manager.cc
diff --git a/components/autofill/core/browser/autofill_manager.cc b/components/autofill/core/browser/autofill_manager.cc
index d599bce07603f84b97bd881bbe88c249078ea123..9279c950364215a351e29882e5f358fae24333d7 100644
--- a/components/autofill/core/browser/autofill_manager.cc
+++ b/components/autofill/core/browser/autofill_manager.cc
@@ -2007,7 +2007,7 @@ void AutofillManager::DeterminePossibleFieldTypesForUpload(
   // 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);
-    ServerFieldTypeSet matching_types;
+    ServerFieldTypeSet matching_types = field->possible_types();

[Roger McFarlane (Chromium), 2017/04/07 03:20:59]

Is there a way to refactor this such that we don't expect the field to magically
have possible_types before having been passed to this method. It bakes in the
assumption that the password manager previously populated this field.

I'd rather see something like

  field.reset_possible_types();
  for (const auto& profile : profiles)
    field.add_possible_types(profile.GetMatchingTypes(value, app_locale));
  for (const auto& card : credit_cards)
    field.add_possible_types(card.GetMatchingTypes(value, app_locale));
  for (const auto& login : logins)
    field.add_possible_type(login.GetMatchingTypes(value, app_locale));

[dvadym, 2017/04/07 09:09:01]

Yeah, it would look better here, but it looks like such structure isn't suitable
for login information: all other autofill types are user personal information
and they are stored in the user profile, on other hand passwords are unique and
they are determined during saving, so we can't match value against profile.
Moreover Password Manager will set only one type - PASSWORD, basically we need
this type here only for finding password forms/fields server-side.

 
     base::string16 value;
     base::TrimWhitespace(field->value, base::TRIM_ALL, &value);