Merge "Fix type for patchNumStr"
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
index e7bf7da..8d64bc0 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
@@ -2480,8 +2480,8 @@
   }
 
   @observe('_patchRange.patchNum')
-  _patchNumChanged(patchNumStr: PatchSetNum) {
-    if (!this._selectedRevision) {
+  _patchNumChanged(patchNumStr?: PatchSetNum) {
+    if (!this._selectedRevision || !patchNumStr) {
       return;
     }
     assertIsDefined(this._change, '_change');