Check for NULL PasswordFormManager* in ManagePasswordsUIController::SavePasswordInternal().

BUG=468474

Review URL: https://codereview.chromium.org/1019943002

Cr-Commit-Position: refs/heads/master@{#321408}

chrome/browser/ui/passwords/manage_passwords_ui_controller.cc

@@ -218,8 +218,11 @@ void ManagePasswordsUIController::ChooseCredential(
 void ManagePasswordsUIController::SavePasswordInternal() {
   password_manager::PasswordFormManager* form_manager =
       passwords_data_.form_manager();
-  DCHECK(form_manager);
-  form_manager->Save();
+  // TODO(vasilii): it's not OK to call SavePassword() when |form_manager| is 0.
+  // If this is a cause of http://crbug.com/468474 then we should hide the
+  // bubble when ManagePasswordsUIController changes its internal state.
+  if (form_manager)
+    form_manager->Save();
 }
 
 void ManagePasswordsUIController::NeverSavePassword() {