Make submit event code work with both jQuery event and native event (#29223) (#29234)

Backport #29223 (no conflict)

web_src/js/features/common-issue-list.js

@@ -40,7 +40,7 @@ export function initCommonIssueListQuickGoto() {
   $form.on('submit', (e) => {
     // if there is no goto button, or the form is submitted by non-quick-goto elements, submit the form directly
     let doQuickGoto = !isElemHidden($goto);
-    const submitter = submitEventSubmitter(e.originalEvent);
+    const submitter = submitEventSubmitter(e);
     if (submitter !== $form[0] && submitter !== $input[0] && submitter !== $goto[0]) doQuickGoto = false;
     if (!doQuickGoto) return;
 

web_src/js/features/repo-diff.js

@@ -58,7 +58,7 @@ function initRepoDiffConversationForm() {
       const formData = new FormData($form[0]);
 
       // if the form is submitted by a button, append the button's name and value to the form data
-      const submitter = submitEventSubmitter(e.originalEvent);
+      const submitter = submitEventSubmitter(e);
       const isSubmittedByButton = (submitter?.nodeName === 'BUTTON') || (submitter?.nodeName === 'INPUT' && submitter.type === 'submit');
       if (isSubmittedByButton && submitter.name) {
         formData.append(submitter.name, submitter.value);

web_src/js/utils/dom.js

@@ -211,6 +211,7 @@ export function loadElem(el, src) {
 const needSubmitEventPolyfill = typeof SubmitEvent === 'undefined';
 
 export function submitEventSubmitter(e) {
+  e = e.originalEvent ?? e; // if the event is wrapped by jQuery, use "originalEvent", otherwise, use the event itself
   return needSubmitEventPolyfill ? (e.target._submitter || null) : e.submitter;
 }