[DevTools] Prepare to pass modified InspectorFrontendHost to inspector app.

Source/devtools/front_end/host/InspectorFrontendHost.js

Index: Source/devtools/front_end/host/InspectorFrontendHost.js
diff --git a/Source/devtools/front_end/host/InspectorFrontendHost.js b/Source/devtools/front_end/host/InspectorFrontendHost.js
index 124fca72480f4387dd946e499bead4dc028f514e..a0196e2282f4dc028aaa452afea1961f8a8fe607 100644
--- a/Source/devtools/front_end/host/InspectorFrontendHost.js
+++ b/Source/devtools/front_end/host/InspectorFrontendHost.js
@@ -632,10 +632,6 @@ WebInspector.InspectorFrontendHostStub.prototype = {
 var InspectorFrontendHost = window.InspectorFrontendHost || null;
 
 (function() {
-    if (window.top) {
-        // FIXME(dgozman): use InspectorAppHost everywhere in inspector app instead of InspectorFrontendHost.
-        InspectorFrontendHost = window.top.InspectorFrontendHost || null;
-    }
     if (!InspectorFrontendHost) {
         // Instantiate stub for web-hosted mode if necessary.
         InspectorFrontendHost = new WebInspector.InspectorFrontendHostStub();