No need to pass event as a parameter

We should stop passing events as a parameter since we cannot call the method programatically without faking or creating an event even when that event is not entirely required.

app/assets/javascripts/gl_dropdown.js

@@ -607,7 +607,7 @@
       return this.dropdown.before($input);
     };
 
-    GitLabDropdown.prototype.selectRowAtIndex = function(e, index) {
+    GitLabDropdown.prototype.selectRowAtIndex = function(index) {
       var $el, selector;
       selector = ".dropdown-content li:not(.divider,.dropdown-header,.separator):eq(" + index + ") a";
       if (this.dropdown.find(".dropdown-toggle-page").length) {
@@ -615,8 +615,6 @@
       }
       $el = $(selector, this.dropdown);
       if ($el.length) {
-        e.preventDefault();
-        e.stopImmediatePropagation();
         return $el.first().trigger('click');
       }
     };
@@ -653,7 +651,7 @@
             return false;
           }
           if (currentKeyCode === 13 && currentIndex !== -1) {
-            return _this.selectRowAtIndex(e, $('.is-focused', _this.dropdown).closest('li').index() - 1);
+            return _this.selectRowAtIndex($('.is-focused', _this.dropdown).closest('li').index() - 1);
           }
         };
       })(this));

app/assets/javascripts/protected_branch_create.js.es6

@@ -16,7 +16,7 @@ class ProtectedBranchCreate {
     });
 
     // Select default
-    $allowedToMergeDropdown.data('glDropdown').selectRowAtIndex(document.createEvent('Event'), 0);
+    $allowedToMergeDropdown.data('glDropdown').selectRowAtIndex(0);
 
     // Allowed to Push dropdowns
     new ProtectedBranchAccessDropdown({
@@ -26,7 +26,7 @@ class ProtectedBranchCreate {
     });
 
     // Select default
-    $allowedToPushDropdown.data('glDropdown').selectRowAtIndex(document.createEvent('Event'), 0);
+    $allowedToPushDropdown.data('glDropdown').selectRowAtIndex(0);
 
     new ProtectedBranchDropdowns({
       $dropdowns: this.$wrap.find('.js-protected-branch-select'),

app/assets/javascripts/protected_branch_select.js.es6

@@ -44,9 +44,9 @@ class ProtectedBranchDropdown {
     this.$protectedBranch.on('click', this.onClickCreateWildcard.bind(this));
   }
 
-  onClickCreateWildcard(e) {
+  onClickCreateWildcard() {
     this.$dropdown.data('glDropdown').remote.execute();
-    this.$dropdown.data('glDropdown').selectRowAtIndex(e, 0);
+    this.$dropdown.data('glDropdown').selectRowAtIndex(0);
   }
 
   getProtectedBranches(term, callback) {