Remove all generic CustomEvents

In the referenced bug we have identified generic CustomEvent as being
harmful. It is similar to allowing `any` as a type.

This is just a random Friday cleanup for technical excellence.

After this change there is only one match for this regexp, which has an
associated TODO: ([^w].|^)CustomEvent([^<]|$)

Release-Notes: skip
Google-Bug-Id: b/265892992
Change-Id: Iff1fb96101900d924533bcecb638cc68174a3462
diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
index f3c23aa..da49af0 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
@@ -116,7 +116,11 @@
 import {sharedStyles} from '../../../styles/shared-styles';
 import {when} from 'lit/directives/when.js';
 import {classMap} from 'lit/directives/class-map.js';
-import {ValueChangedEvent} from '../../../types/events';
+import {
+  AddReviewerEvent,
+  RemoveReviewerEvent,
+  ValueChangedEvent,
+} from '../../../types/events';
 import {customElement, property, state, query} from 'lit/decorators.js';
 import {subscribe} from '../../lit/subscription-controller';
 import {configModelToken} from '../../../models/config/config-model';
@@ -723,17 +727,19 @@
     // Plugins on reply-reviewers endpoint can take advantage of these
     // events to add / remove reviewers
 
-    this.addEventListener('add-reviewer', e => {
+    this.addEventListener('add-reviewer', (e: AddReviewerEvent) => {
+      const reviewer = e.detail.reviewer;
       // Only support account type, see more from:
       // elements/shared/gr-account-list/gr-account-list.js#addAccountItem
       this.reviewersList?.addAccountItem({
-        account: (e as CustomEvent).detail.reviewer,
+        account: reviewer,
         count: 1,
       });
     });
 
-    this.addEventListener('remove-reviewer', e => {
-      this.reviewersList?.removeAccount((e as CustomEvent).detail.reviewer);
+    this.addEventListener('remove-reviewer', (e: RemoveReviewerEvent) => {
+      const reviewer = e.detail.reviewer;
+      this.reviewersList?.removeAccount(reviewer);
     });
   }