Fix template problems with gr-search-bar

Change-Id: I8d67f8434d80c81bc4d1c5fa139ddc222d3c0b84
diff --git a/polygerrit-ui/app/BUILD b/polygerrit-ui/app/BUILD
index 4d0bb1f..20d66a5 100644
--- a/polygerrit-ui/app/BUILD
+++ b/polygerrit-ui/app/BUILD
@@ -108,7 +108,6 @@
     "elements/change/gr-thread-list/gr-thread-list_html.ts",
     "elements/checks/gr-hovercard-run_html.ts",
     "elements/core/gr-main-header/gr-main-header_html.ts",
-    "elements/core/gr-search-bar/gr-search-bar_html.ts",
     "elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog_html.ts",
     "elements/diff/gr-diff-builder/gr-diff-builder-element_html.ts",
     "elements/diff/gr-diff-host/gr-diff-host_html.ts",
diff --git a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.ts b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.ts
index e30e75e..841089e 100644
--- a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.ts
+++ b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.ts
@@ -180,7 +180,7 @@
   accountSuggestions: SuggestionProvider = () => Promise.resolve([]);
 
   @property({type: String})
-  _inputVal?: string;
+  _inputVal = '';
 
   @property({type: Number})
   _threshold = 1;