DevTools: Do not re-create CSSWorkspaceBinding TargetInfo on MainFrameNavigated

Source/devtools/front_end/sdk/CSSWorkspaceBinding.js

 // Copyright 2014 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
  * @implements {WebInspector.TargetManager.Observer}
  */
 WebInspector.CSSWorkspaceBinding = function()
 {
@@ skipping 53 matching lines @@
         }
         return targetInfo._ensureInfoForHeader(header);
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _mainFrameCreatedOrNavigated: function(event)
     {
         var target = /** @type {!WebInspector.ResourceTreeModel} */ (event.target).target();
-        var info = this._targetToTargetInfo.remove(target);
-        if (info)
-            info._dispose();
-        this._targetToTargetInfo.put(target, new WebInspector.CSSWorkspaceBinding.TargetInfo(target, WebInspector.workspace, WebInspector.networkWorkspaceBinding));
+        this._targetToTargetInfo.get(target)._reset();
     },
 
     /**
      * @param {!WebInspector.CSSStyleSheetHeader} header
      */
     updateLocations: function(header)
     {
         var info = this._headerInfo(header);
         if (info)
             info._updateLocations();
@@ skipping 139 matching lines @@
         var info = this._headerInfoById.get(header.id);
         if (!info) {
             info = new WebInspector.CSSWorkspaceBinding.HeaderInfo(header);
             this._headerInfoById.put(header.id, info);
         }
         return info;
     },
 
     _dispose: function()
     {
+        this._reset();
         this._target.cssModel.removeEventListener(WebInspector.CSSStyleModel.Events.StyleSheetAdded, this._styleSheetAdded, this);
         this._target.cssModel.removeEventListener(WebInspector.CSSStyleModel.Events.StyleSheetRemoved, this._styleSheetRemoved, this);
+    },
+
+    _reset: function()
+    {
+        this._headerInfoById.clear();
     }
 }
 
 /**
  * @constructor
  * @param {!WebInspector.CSSStyleSheetHeader} header
  */
 WebInspector.CSSWorkspaceBinding.HeaderInfo = function(header)
 {
     this._header = header;
@@ skipping 140 matching lines @@
         this._cssModel.removeEventListener(WebInspector.CSSStyleModel.Events.StyleSheetRemoved, this._styleSheetRemoved, this);
     },
 
     __proto__: WebInspector.LiveLocation.prototype
 }
 
 /**
  * @type {!WebInspector.CSSWorkspaceBinding}
  */
 WebInspector.cssWorkspaceBinding;