(2nd try) Add a helper class that keeps per-profile information for FileSystem API

chrome/test/testing_profile.h

 // Copyright (c) 2010 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_TEST_TESTING_PROFILE_H_
 #define CHROME_TEST_TESTING_PROFILE_H_
 #pragma once
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
@@ skipping 138 matching lines @@
     return NULL;
   }
   virtual PrefService* GetPrefs();
   virtual TemplateURLModel* GetTemplateURLModel() {
     return template_url_model_.get();
   }
   virtual TemplateURLFetcher* GetTemplateURLFetcher() { return NULL; }
   virtual history::TopSites* GetTopSites();
   virtual DownloadManager* GetDownloadManager() { return NULL; }
   virtual PersonalDataManager* GetPersonalDataManager() { return NULL; }
+  virtual FileSystemHostContext* GetFileSystemHostContext() { return NULL; }
   virtual bool HasCreatedDownloadManager() const { return false; }
   virtual void InitThemes();
   virtual void SetTheme(Extension* extension) {}
   virtual void SetNativeTheme() {}
   virtual void ClearTheme() {}
   virtual Extension* GetTheme() { return NULL; }
   virtual BrowserThemeProvider* GetThemeProvider() {
     InitThemes();
     return theme_provider_.get();
   }
@@ skipping 187 matching lines @@
 
   virtual ProfileId GetRuntimeId() {
     return original_profile_->GetRuntimeId();
   }
 
  protected:
   Profile* original_profile_;
 };
 
 #endif  // CHROME_TEST_TESTING_PROFILE_H_