Add thread checks to the IPC channel....

base/non_thread_safe.h

 // Copyright (c) 2006-2008 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 BASE_NON_THREAD_SAFE_H__
 #define BASE_NON_THREAD_SAFE_H__
 
 #include "base/logging.h"
 #include "base/platform_thread.h"
 
@@ skipping 14 matching lines @@
 // }
 //
 // In Release mode, CalledOnValidThread will always return true.
 //
 #ifndef NDEBUG
 class NonThreadSafe {
  public:
   NonThreadSafe();
   ~NonThreadSafe();
 
- protected:
   bool CalledOnValidThread() const;
 
  private:
   PlatformThreadId valid_thread_id_;
 };
 #else
 // Do nothing in release mode.
 class NonThreadSafe {
  public:
   NonThreadSafe() {}
   ~NonThreadSafe() {}
 
- protected:
   bool CalledOnValidThread() const {
     return true;
   }
 };
 #endif  // NDEBUG
 
 #endif  // BASE_NON_THREAD_SAFE_H__