DevTools: get rid of WebInspector.cssModel, use target models instead

Source/devtools/front_end/sdk/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 1690 matching lines @@
     requestContent: function(callback)
     {
         this._cssModel._agent.getStyleSheetText(this.id, textCallback.bind(this));
 
         /**
          * @this {WebInspector.CSSStyleSheetHeader}
          */
         function textCallback(error, text)
         {
             if (error) {
-                WebInspector.console.addErrorMessage("Failed to get text for stylesheet " + this.id + ": " + error);
+                WebInspector.console.error("Failed to get text for stylesheet " + this.id + ": " + error);
                 text = "";
                 // Fall through.
             }
             text = this._trimSourceURL(text);
             callback(text);
         }
     },
 
     /**
      * @override
@@ skipping 118 matching lines @@
             for (var i = 0; i < callbacks.length; ++i)
                 callbacks[i](computedStyle);
         }
     }
 }
 
 /**
  * @type {!WebInspector.CSSStyleModel}
  */
 WebInspector.cssModel;