[Password Manager] Send username correction votes

components/autofill/core/common/password_form.cc

Index: components/autofill/core/common/password_form.cc
diff --git a/components/autofill/core/common/password_form.cc b/components/autofill/core/common/password_form.cc
index 3969e1ff4e4a41f9adba4503b0f339986e3e0a6c..17892915c65c8f852b94dd2ad7648843be18e296 100644
--- a/components/autofill/core/common/password_form.cc
+++ b/components/autofill/core/common/password_form.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <algorithm>
 #include <ostream>
 #include <sstream>
 
@@ -40,9 +41,9 @@ void PasswordFormToJSON(const PasswordForm& form,
                      form.new_password_value_is_default);
   target->SetBoolean("new_password_marked_by_site",
                      form.new_password_marked_by_site);
-  target->SetString("other_possible_usernames",
-                    base::JoinString(form.other_possible_usernames,
-                                     base::ASCIIToUTF16("|")));
+  target->SetString(
+      "other_possible_usernames",
+      OtherPossibleUsernamesToString(form.other_possible_usernames));
   target->SetBoolean("blacklisted", form.blacklisted_by_user);
   target->SetBoolean("preferred", form.preferred);
   target->SetDouble("date_created", form.date_created.ToDoubleT());
@@ -167,6 +168,16 @@ bool LessThanUniqueKey::operator()(
   return left->origin < right->origin;
 }
 
+base::string16 OtherPossibleUsernamesToString(
+    const PossibleUsernamesVector& possible_usernames) {
+  std::vector<base::string16> pairs(possible_usernames.size());
+  std::transform(possible_usernames.begin(), possible_usernames.end(),
+                 pairs.begin(), [](const PossibleUsernamePair& p) {
+                   return p.first + base::ASCIIToUTF16("+") + p.second;
+                 });
+  return base::JoinString(pairs, base::ASCIIToUTF16(", "));
+}
+
 std::ostream& operator<<(std::ostream& os, PasswordForm::Layout layout) {
   switch (layout) {
     case PasswordForm::Layout::LAYOUT_OTHER: