[DevTools] Remove SDKModels' fromTarget methods

third_party/WebKit/Source/devtools/front_end/sdk/CSSStyleSheetHeader.js

 // Copyright 2016 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.
 /**
  * @implements {Common.ContentProvider}
  * @unrestricted
  */
 SDK.CSSStyleSheetHeader = class {
   /**
    * @param {!SDK.CSSModel} cssModel
@@ skipping 30 matching lines @@
   }
 
   /**
    * @param {string=} sourceMapURL
    */
   setSourceMapURL(sourceMapURL) {
     this.sourceMapURL = sourceMapURL;
   }
 
   /**
-   * @return {!SDK.Target}
-   */
-  target() {
-    return this._cssModel.target();
-  }
-
-  /**
    * @return {!SDK.CSSModel}
    */
   cssModel() {
     return this._cssModel;
   }
 
   /**
    * @return {boolean}
    */
   isAnonymousInlineStyleSheet() {
     return !this.resourceURL() && !this._cssModel.sourceMapManager().sourceMapForClient(this);
   }
 
   /**
    * @return {string}
    */
   resourceURL() {
     return this.isViaInspector() ? this._viaInspectorResourceURL() : this.sourceURL;
   }
 
   /**
    * @return {string}
    */
   _viaInspectorResourceURL() {
-    var resourceTreeModel = SDK.ResourceTreeModel.fromTarget(this.target());
-    var frame = resourceTreeModel.frameForId(this.frameId);
+    var frame = this._cssModel.target().model(SDK.ResourceTreeModel).frameForId(this.frameId);
     console.assert(frame);
     var parsedURL = new Common.ParsedURL(frame.url);
     var fakeURL = 'inspector://' + parsedURL.host + parsedURL.folderPathComponents;
     if (!fakeURL.endsWith('/'))
       fakeURL += '/';
     fakeURL += 'inspector-stylesheet';
     return fakeURL;
   }
 
   /**
@@ skipping 53 matching lines @@
     this.requestContent().then(performSearch);
   }
 
   /**
    * @return {boolean}
    */
   isViaInspector() {
     return this.origin === 'inspector';
   }
 };