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 0c0d90be38fd42d84297f5f8acac42ceaa7edee7..a137044e6cee718c77b96572c36a7ba618f39f04 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();
 
     base::string16 value;
     base::TrimWhitespace(field->value, base::TRIM_ALL, &value);