Refactor show-alert, page-error events

Change-Id: I38b55a8ceaa5819742e819cea0349fcecfb4b1ce
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 12f8021..f42adc6 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
@@ -110,7 +110,7 @@
 import {isAttentionSetEnabled} from '../../../utils/attention-set-util';
 import {CODE_REVIEW, getMaxAccounts} from '../../../utils/label-util';
 import {isUnresolved} from '../../../utils/comment-util';
-import {fire, EventType} from '../../../utils/event-util';
+import {fireAlert} from '../../../utils/event-util';
 
 const STORAGE_DEBOUNCE_INTERVAL_MS = 400;
 
@@ -549,7 +549,7 @@
             const moveTo = isReviewer ? 'reviewer' : 'CC';
             const id = account.name || account.email || key;
             const message = `${id} moved from ${moveFrom} to ${moveTo}.`;
-            fire(this, EventType.SHOW_ALERT, message);
+            fireAlert(this, message);
           }
         }
       }
@@ -1270,7 +1270,7 @@
       return;
     }
     if (this._sendDisabled) {
-      fire(this, EventType.SHOW_ALERT, EMPTY_REPLY_MESSAGE);
+      fireAlert(this, EMPTY_REPLY_MESSAGE);
       return;
     }
     return this.send(this._includeComments, this.canBeStarted)