FIX: properly check key values for shortcuts (#463)

- Update angle bracket components to use vanilla attributes where possible
- Update how we check for key value after changing to `on "change"` from `onChange`

assets/javascripts/discourse-assign/controllers/assign-user.js

@@ -72,7 +72,7 @@ export default Controller.extend(ModalFunctionality, {
   },
 
   @action
-  handleTextAreaKeydown(value, event) {
+  handleTextAreaKeydown(event) {
     if ((event.ctrlKey || event.metaKey) && event.key === "Enter") {
       this.assign();
     }

assets/javascripts/discourse/templates/modal/assign-user.hbs

@@ -1,4 +1,4 @@
-<DModalBody @class="assign">
+<DModalBody class="assign">
   <div>
     <div class="control-group {{if this.assigneeError 'assignee-error'}}">
       <label>{{i18n "discourse_assign.assign_modal.assignee_label"}}</label>
@@ -61,16 +61,16 @@
 </DModalBody>
 
 <div class="modal-footer">
-  {{d-button
-    label=(if
+  <DButton
+    @label={{if
       model.reassign
       "discourse_assign.reassign.title"
       "discourse_assign.assign_modal.assign"
-    )
-    icon=inviteIcon
-    action=(action "assign")
+    }}
+    @icon={{inviteIcon}}
+    @action={{this.assign}}
     class="btn-primary"
-    disabled=disabled
-  }}
+    @disabled={{disabled}}
+  />
   <DModalCancel @close={{route-action "closeModal"}} />
 </div>