Don't switch to CF's active document for frames or iframes....

chrome_frame/protocol_sink_wrap.h

 // Copyright (c) 2009 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.
 
 #ifndef CHROME_FRAME_PROTOCOL_SINK_WRAP_H_
 #define CHROME_FRAME_PROTOCOL_SINK_WRAP_H_
 
 #include <exdisp.h>
 #include <urlmon.h>
 #include <atlbase.h>
@@ skipping 150 matching lines @@
     UNDETERMINED,
     CHROME,
     OTHER
   };
 
   typedef std::map<IInternetProtocol*, ProtocolSinkWrap*> ProtocolSinkMap;
   static const int kMaxContentSniffLength = 1024;
 
   static scoped_refptr<ProtocolSinkWrap> InstanceFromProtocol(
       IInternetProtocol* protocol);
-  static HRESULT WebBrowserFromProtocolSink(IInternetProtocolSink* sink,
-      IWebBrowser2** web_browser);
   static ScopedComPtr<IInternetProtocolSink> MaybeWrapSink(
       IInternetProtocol* protocol, IInternetProtocolSink* prot_sink,
       const wchar_t* url);
 
   void DetermineRendererType();
   HRESULT OnReadImpl(void* buffer, ULONG size, ULONG* size_read,
       InternetProtocol_Read_Fn orig_read);
 
   bool is_undetermined() const {
     return (UNDETERMINED == renderer_type_);
@@ skipping 45 matching lines @@
   // TODO(joshia): Replace with Lock
   static CComAutoCriticalSection sink_map_lock_;
 
   std::wstring url_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ProtocolSinkWrap);
 };
 
 #endif  // CHROME_FRAME_PROTOCOL_SINK_WRAP_H_