DevTools: fix leaking CSSRules through LiveLocations

Source/devtools/front_end/CSSStyleModel.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 655 matching lines @@
             return this._header.rawLocationToUILocation(cssLocation.lineNumber, cssLocation.columnNumber);
         var uiSourceCode = WebInspector.workspace.uiSourceCodeForURL(cssLocation.url);
         if (!uiSourceCode)
             return null;
         return new WebInspector.UILocation(uiSourceCode, cssLocation.lineNumber, cssLocation.columnNumber);
     },
 
     dispose: function()
     {
         WebInspector.LiveLocation.prototype.dispose.call(this);
+        if (this._header)
+            this._header._removeLocation(this);
         this._model.removeEventListener(WebInspector.CSSStyleModel.Events.StyleSheetAdded, this._styleSheetAdded, this);
         this._model.removeEventListener(WebInspector.CSSStyleModel.Events.StyleSheetRemoved, this._styleSheetRemoved, this);
     },
 
     __proto__: WebInspector.LiveLocation.prototype
 }
 
 /**
  * @constructor
  * @implements {WebInspector.RawLocation}
@@ skipping 920 matching lines @@
             for (var i = 0; i < callbacks.length; ++i)
                 callbacks[i](computedStyle);
         }
     }
 }
 
 /**
  * @type {!WebInspector.CSSStyleModel}
  */
 WebInspector.cssModel;