DevTools: Remove unused variables. Disallow unused variables with eslint

third_party/WebKit/Source/devtools/front_end/animation/AnimationUI.js

 // Copyright (c) 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
  */
 Animation.AnimationUI = class {
   /**
    * @param {!Animation.AnimationModel.Animation} animation
    * @param {!Animation.AnimationTimeline} timeline
@@ skipping 185 matching lines @@
       var stepFunction = Animation.AnimationTimeline.StepTimingFunction.parse(easing);
       group.removeChildren();
       /** @const */ var offsetMap = {'start': 0, 'middle': 0.5, 'end': 1};
       /** @const */ var offsetWeight = offsetMap[stepFunction.stepAtPosition];
       for (var i = 0; i < stepFunction.steps; i++)
         createStepLine(group, (i + offsetWeight) * width / stepFunction.steps, this._color);
     }
   }
 
   redraw() {
-    var durationWithDelay =
-        this._delay() + this._duration() * this._animation.source().iterations() + this._animation.source().endDelay();
     var maxWidth = this._timeline.width() - Animation.AnimationUI.Options.AnimationMargin;
 
     this._svg.setAttribute('width', (maxWidth + 2 * Animation.AnimationUI.Options.AnimationMargin).toFixed(2));
     this._activeIntervalGroup.style.transform =
         'translateX(' + (this._delay() * this._timeline.pixelMsRatio()).toFixed(2) + 'px)';
 
     this._nameElement.style.transform = 'translateX(' +
         (this._delay() * this._timeline.pixelMsRatio() + Animation.AnimationUI.Options.AnimationMargin).toFixed(2) +
         'px)';
     this._nameElement.style.width = (this._duration() * this._timeline.pixelMsRatio()).toFixed(2) + 'px';
@@ skipping 188 matching lines @@
   'Light Blue': Common.Color.parse('#03A9F4'),
   'Deep Orange': Common.Color.parse('#FF5722'),
   'Blue': Common.Color.parse('#5677FC'),
   'Lime': Common.Color.parse('#CDDC39'),
   'Blue Grey': Common.Color.parse('#607D8B'),
   'Pink': Common.Color.parse('#E91E63'),
   'Green': Common.Color.parse('#0F9D58'),
   'Brown': Common.Color.parse('#795548'),
   'Cyan': Common.Color.parse('#00BCD4')
 };