Switch the change view to listening to the view model

Release-Notes: skip
Google-Bug-Id: b/244279450
Change-Id: I30cfb94f4ac5083c68f1125df7242c8bf6045ba2

polygerrit-ui/app/models/views/change.ts

diff --git a/polygerrit-ui/app/models/views/change.ts b/polygerrit-ui/app/models/views/change.ts
index 51b1862..7f75d83 100644
--- a/polygerrit-ui/app/models/views/change.ts
+++ b/polygerrit-ui/app/models/views/change.ts
@@ -41,10 +41,6 @@
   usp?: string;
 }
 
-const DEFAULT_STATE: ChangeViewState = {
-  view: GerritView.CHANGE,
-};
-
 export function createChangeUrl(state: Omit<ChangeViewState, 'view'>) {
   let range = getPatchRangeExpression(state);
   if (range.length) {
@@ -84,8 +80,8 @@
 export const changeViewModelToken =
   define<ChangeViewModel>('change-view-model');
 
-export class ChangeViewModel extends Model<ChangeViewState> {
+export class ChangeViewModel extends Model<ChangeViewState | undefined> {
   constructor() {
-    super(DEFAULT_STATE);
+    super(undefined);
   }
 }