DevTools: Remove unused variables. Disallow unused variables with eslint

third_party/WebKit/Source/devtools/front_end/network/NetworkOverview.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 /**
  * @unrestricted
  */
 Network.NetworkOverview = class extends UI.TimelineOverviewBase {
   constructor() {
     super();
     this.element.classList.add('network-overview');
@@ skipping 156 matching lines @@
     var newBoundary =
         new Network.NetworkTimeBoundary(this._calculator.minimumBoundary(), this._calculator.maximumBoundary());
     if (!this._lastBoundary || !newBoundary.equals(this._lastBoundary)) {
       var span = this._calculator.boundarySpan();
       while (this._span < span)
         this._span *= 1.25;
       this._calculator.setBounds(this._calculator.minimumBoundary(), this._calculator.minimumBoundary() + this._span);
       this._lastBoundary =
           new Network.NetworkTimeBoundary(this._calculator.minimumBoundary(), this._calculator.maximumBoundary());
       if (this._windowStart || this._windowEnd) {
         this._restoringWindow = true;

[dgozman, 2016/12/10 02:15:14]

Let's maybe remove more now?

[einbinder, 2016/12/12 20:41:18]

Done.

-        var startTime = this._calculator.minimumBoundary();
-        var totalTime = this._calculator.boundarySpan();

[dgozman, 2016/12/10 02:15:14]

Let's double-check for side-effects.

[einbinder, 2016/12/12 20:41:18]

Done.

-        var left = (this._windowStart - startTime) / totalTime;
-        var right = (this._windowEnd - startTime) / totalTime;
         this._restoringWindow = false;
       }
     }
 
     var context = this._canvas.getContext('2d');
     var calculator = this._calculator;
     var linesByType = {};
     var paddingTop = 2;
 
     /**
@@ skipping 97 matching lines @@
     }
     context.restore();
   }
 };
 
 /** @type {number} */
 Network.NetworkOverview._bandHeight = 3;
 
 /** @typedef {{start: number, end: number}} */
 Network.NetworkOverview.Window;