gr-editor-view: Use change-model for change param

Release-Notes: skip
Change-Id: I50cb472127b8fd106d3fcc9a55f96b001ed54840
diff --git a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.ts b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.ts
index cf555eb..66019ef 100644
--- a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.ts
+++ b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.ts
@@ -117,6 +117,11 @@
     });
     subscribe(
       this,
+      () => this.getChangeModel().change$,
+      x => (this.change = x)
+    );
+    subscribe(
+      this,
       () => this.getUserModel().editPreferences$,
       editPreferences => (this.editPrefs = editPreferences)
     );
@@ -336,17 +341,10 @@
     });
 
     const promises = [];
-    promises.push(this.getChangeDetail());
     promises.push(this.getFileData());
     return Promise.all(promises);
   }
 
-  private async getChangeDetail() {
-    const changeNum = this.viewState?.changeNum;
-    assertIsDefined(changeNum, 'change number');
-    this.change = await this.restApiService.getChangeDetail(changeNum);
-  }
-
   private navigateToChangeIfEdit() {
     if (!this.change) return;
     if (!changeIsMerged(this.change) && !changeIsAbandoned(this.change)) return;
diff --git a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.ts b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.ts
index a2c92c5..c86f02f 100644
--- a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.ts
+++ b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.ts
@@ -37,7 +37,6 @@
 
   let savePathStub: sinon.SinonStub;
   let saveFileStub: sinon.SinonStub;
-  let changeDetailStub: sinon.SinonStub;
   let navigateStub: sinon.SinonStub;
   let storageService: StorageService;
 
@@ -45,7 +44,6 @@
     element = await fixture(html`<gr-editor-view></gr-editor-view>`);
     savePathStub = stubRestApi('renameFileInChangeEdit');
     saveFileStub = stubRestApi('saveChangeEdit');
-    changeDetailStub = stubRestApi('getChangeDetail');
     navigateStub = sinon.stub(element, 'viewEditInChangeView');
     element.viewState = {
       ...createEditViewState(),
@@ -127,7 +125,6 @@
 
   suite('viewStateChanged', () => {
     test('good view state proceed', async () => {
-      changeDetailStub.returns(Promise.resolve({}));
       const fileStub = sinon.stub(element, 'getFileData').callsFake(() => {
         element.content = 'text';
         element.newContent = 'text';
@@ -140,8 +137,6 @@
 
       await element.updateComplete;
 
-      const changeNum = 42 as NumericChangeId;
-      assert.deepEqual(changeDetailStub.lastCall.args[0], changeNum);
       assert.isTrue(fileStub.called);
 
       return promises?.then(() => {