DevTools: enable private field checks as a part of compilation.

third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js

Index: third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js
diff --git a/third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js b/third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js
index adf618e7e7f409f8953b330c0271ab8ae7c1f906..960a64a2f8cf666d74819006b93a15a4ecc8eb64 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui_lazy/ViewportDataGrid.js
@@ -306,18 +306,13 @@ UI.ViewportDataGridNode = class extends UI.DataGridNode {
    * @return {!Element}
    */
   element() {
-    if (!this._element) {
-      this.createElement();
-      this.createCells();
+    var hadElement = !!this._element;
+    var element = this.createElement();

[alph, 2016/12/12 23:41:37]

You don't need to create an element if there's already one.

+    if (!hadElement || this._stale) {
+      this.createCells(element);
       this._stale = false;
     }
-
-    if (this._stale) {
-      this.createCells();
-      this._stale = false;
-    }
-
-    return /** @type {!Element} */ (this._element);
+    return element;
   }
 
   /**