Don't allow the empty new password to overwrite the existing one.

components/password_manager/core/browser/password_manager.cc

Index: components/password_manager/core/browser/password_manager.cc
diff --git a/components/password_manager/core/browser/password_manager.cc b/components/password_manager/core/browser/password_manager.cc
index be903b8f4d2f642e3314a13f78edbcca58b18d57..01213bb818fa21e91f3e9fc686d37891494326ef 100644
--- a/components/password_manager/core/browser/password_manager.cc
+++ b/components/password_manager/core/browser/password_manager.cc
@@ -173,7 +173,8 @@ void PasswordManager::ProvisionallySavePassword(const PasswordForm& form) {
   }
 
   // No password to save? Then don't.
-  if (form.password_value.empty() && form.new_password_value.empty()) {
+  if ((form.new_password_element.empty() && form.password_value.empty()) ||
+      (!form.new_password_element.empty() && form.new_password_value.empty())) {
     RecordFailure(EMPTY_PASSWORD, form.origin.host(), logger.get());
     return;
   }