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

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

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 490 matching lines @@
   height() {
     return this._canvas.height;
   }
 
   /** @return {!CanvasRenderingContext2D} */
   context() {
     return this._context;
   }
 
   /**
+   * @protected
+   * @return {?UI.TimelineOverviewCalculator}
+   */
+  calculator() {
+    return this._calculator;
+  }
+
+  /**
    * @override
    */
   update() {
     this.resetCanvas();
   }
 
   /**
    * @override
    */
   dispose() {
@@ skipping 69 matching lines @@
       left: haveRecords && startTime ? Math.min((startTime - absoluteMin) / timeSpan, 1) : 0,
       right: haveRecords && endTime < Infinity ? (endTime - absoluteMin) / timeSpan : 1
     };
   }
 
   resetCanvas() {
     this._canvas.width = this.element.clientWidth * window.devicePixelRatio;
     this._canvas.height = this.element.clientHeight * window.devicePixelRatio;
   }
 };