DevTools: Remove unused variables. Disallow unused variables with eslint

third_party/WebKit/Source/devtools/front_end/audits/AuditRules.js

 /*
  * Copyright (C) 2010 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 66 matching lines @@
   /**
    * @override
    * @param {!SDK.Target} target
    * @param {!Array.<!SDK.NetworkRequest>} requests
    * @param {!Audits.AuditRuleResult} result
    * @param {function(?Audits.AuditRuleResult)} callback
    * @param {!Common.Progress} progress
    */
   doRun(target, requests, result, callback, progress) {
     var totalSavings = 0;
-    var compressedSize = 0;
-    var candidateSize = 0;
     var summary = result.addChild('', true);
     for (var i = 0, length = requests.length; i < length; ++i) {
       var request = requests[i];
       if (request.cached() || request.statusCode === 304)
         continue;  // Do not test cached resources.
       if (this._shouldCompress(request)) {
         var size = request.resourceSize;
-        candidateSize += size;
-        if (this._isCompressed(request)) {
-          compressedSize += size;
+        if (this._isCompressed(request))
           continue;
-        }
         var savings = 2 * size / 3;
         totalSavings += savings;
         summary.addFormatted('%r could save ~%s', request.url, Number.bytesToString(savings));
         result.violationCount++;
       }
     }
     if (!totalSavings) {
       callback(null);
       return;
     }
@@ skipping 1367 matching lines @@
             Number.bytesToString(cookieBytes)),
         true);
     entry.addURLs(badUrls);
     result.violationCount = badUrls.length;
   }
 
   _collectorCallback(matchingResourceData, request, cookie) {
     matchingResourceData[request.url] = (matchingResourceData[request.url] || 0) + cookie.size();
   }
 };