DevTools: use target-based model accessors only.

Source/devtools/front_end/sdk/SourceMap.js

 /*
  * Copyright (C) 2012 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 76 matching lines @@
 
 /**
  * @param {!WebInspector.Target} target
  * @param {string} sourceMapURL
  * @param {string} compiledURL
  * @param {function(?WebInspector.SourceMap)} callback
  * @this {WebInspector.SourceMap}
  */
 WebInspector.SourceMap.load = function(target, sourceMapURL, compiledURL, callback)
 {
-    var resourceTreeModel = WebInspector.resourceTreeModel;
+    var resourceTreeModel = target.resourceTreeModel;
     if (resourceTreeModel.cachedResourcesLoaded())
         loadResource();
     else
         resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, cachedResourcesLoaded);
 
     function cachedResourcesLoaded()
     {
         resourceTreeModel.removeEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, cachedResourcesLoaded);
         loadResource();
     }
@@ skipping 276 matching lines @@
     },
 
     /**
      * @return {boolean}
      */
     hasNext: function()
     {
         return this._position < this._string.length;
     }
 }