Remove unused securityState code in WebInspector.SecurityModel.

Source/devtools/front_end/security/SecurityModel.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.
 
 /**
  * @constructor
  * @extends {WebInspector.SDKModel}
  * @param {!WebInspector.Target} target
  */
 WebInspector.SecurityModel = function(target)
 {
     WebInspector.SDKModel.call(this, WebInspector.SecurityModel, target);
     this._dispatcher = new WebInspector.SecurityDispatcher(this);
     this._securityAgent = target.securityAgent();
     target.registerSecurityDispatcher(this._dispatcher);
     this._securityAgent.enable();
-
-    this._securityState = SecurityAgent.SecurityState.Unknown;
 }
 
 WebInspector.SecurityModel.EventTypes = {
     SecurityStateChanged: "SecurityStateChanged"
 }
 
 WebInspector.SecurityModel.prototype = {
-    /**
-     * @return {!SecurityAgent.SecurityState} securityState
-     */
-    securityState: function()
-    {
-        return /** @type {!SecurityAgent.SecurityState} */ (this._securityState);
-    },
-
     __proto__: WebInspector.SDKModel.prototype
 }
 
 /**
  * @param {!WebInspector.Target} target
  * @return {?WebInspector.SecurityModel}
  */
 WebInspector.SecurityModel.fromTarget = function(target)
 {
     var model = /** @type {?WebInspector.SecurityModel} */ (target.model(WebInspector.SecurityModel));
@@ skipping 33 matching lines @@
                 explanations.push({
                     "securityState": mixedContentStatus.displayedInsecureContentStyle,
                     "summary": WebInspector.UIString("Mixed Content"),
                     "description": WebInspector.UIString("The site includes HTTP resources.")
                 });
             }
         }
         this._model.dispatchEventToListeners(WebInspector.SecurityModel.EventTypes.SecurityStateChanged, data);
     }
 }