Revert of [DevTools] Inject element into toolbox window, do not load modules there.

Source/devtools/front_end/main/AdvancedApp.js

Index: Source/devtools/front_end/main/AdvancedApp.js
diff --git a/Source/devtools/front_end/main/AdvancedApp.js b/Source/devtools/front_end/main/AdvancedApp.js
index d03bb0ac3c8b32df8a4395944a25cc7acf602f28..2dae0138fb781af5e8988870e554aafd8f32c03e 100644
--- a/Source/devtools/front_end/main/AdvancedApp.js
+++ b/Source/devtools/front_end/main/AdvancedApp.js
@@ -88,24 +88,14 @@
     },
 
     /**
-     * @param {!Element} rootElement
-     * @override
-     */
-    toolboxLoaded: function(rootElement)
-    {
-        var inspectedPagePlaceholder = new WebInspector.InspectedPagePlaceholder();
-        inspectedPagePlaceholder.addEventListener(WebInspector.InspectedPagePlaceholder.Events.Update, this._onSetInspectedPageBounds.bind(this, true));
-        this._toolboxResponsiveDesignView = new WebInspector.ResponsiveDesignView(inspectedPagePlaceholder);
-        this._toolboxResponsiveDesignView.show(rootElement);
+     * @param {!WebInspector.ResponsiveDesignView} responsiveDesignView
+     * @param {!WebInspector.InspectedPagePlaceholder} placeholder
+     */
+    toolboxLoaded: function(responsiveDesignView, placeholder)
+    {
+        this._toolboxResponsiveDesignView = responsiveDesignView;
+        placeholder.addEventListener(WebInspector.InspectedPagePlaceholder.Events.Update, this._onSetInspectedPageBounds.bind(this, true));
         this._updatePageResizer();
-    },
-
-    /**
-     * @return {!InspectorFrontendHostAPI}
-     */
-    inspectorFrontendHost: function()
-    {
-        return window.InspectorFrontendHost;
     },
 
     _updatePageResizer: function()