Fix template problems with gr-confirm-revert-dialog

Change-Id: Ide660badce62d0663fb44e0dd93c5b5bb019a89f
diff --git a/polygerrit-ui/app/BUILD b/polygerrit-ui/app/BUILD
index 1e1ddab..6fc95de 100644
--- a/polygerrit-ui/app/BUILD
+++ b/polygerrit-ui/app/BUILD
@@ -96,7 +96,6 @@
     "elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog_html.ts",
     "elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog_html.ts",
     "elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_html.ts",
-    "elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_html.ts",
     "elements/change/gr-file-list-header/gr-file-list-header_html.ts",
     "elements/change/gr-file-list/gr-file-list_html.ts",
     "elements/change/gr-label-score-row/gr-label-score-row_html.ts",
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.ts b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.ts
index 450551b..b971039 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.ts
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.ts
@@ -59,7 +59,7 @@
   /* The revert message updated by the user
       The default value is set by the dialog */
   @property({type: String})
-  _message?: string;
+  _message = '';
 
   @property({type: Number})
   _revertType = RevertType.REVERT_SINGLE_CHANGE;
@@ -198,7 +198,7 @@
     this._message = this._revertMessages[RevertType.REVERT_SUBMISSION];
   }
 
-  _handleConfirmTap(e: MouseEvent) {
+  _handleConfirmTap(e: Event) {
     e.preventDefault();
     e.stopPropagation();
     if (this._message === this._originalRevertMessages[this._revertType]) {
@@ -218,7 +218,7 @@
     );
   }
 
-  _handleCancelTap(e: MouseEvent) {
+  _handleCancelTap(e: Event) {
     e.preventDefault();
     e.stopPropagation();
     this.dispatchEvent(
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_html.ts b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_html.ts
index 3ec4f2c..b2acff2 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_html.ts
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_html.ts
@@ -85,8 +85,8 @@
           <label for="revertSubmission" class="label revertSubmission">
             Revert entire submission ([[_changesCount]] Changes)
           </label>
-        </div></template
-      >
+        </div>
+      </template>
       <gr-endpoint-decorator name="confirm-revert-change">
         <label for="messageInput"> Revert Commit Message </label>
         <iron-autogrow-textarea