Add RegisterMountPointProvider and TestMountPointProvider for testing

BUG=none
TEST=none, I'll convert some tests to use it once it's submitted

Review URL: https://chromiumcodereview.appspot.com/10386069

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@136551 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/webkit/fileapi/sandbox_mount_point_provider.h b/webkit/fileapi/sandbox_mount_point_provider.h
index 5fed7eca..63c386f3 100644
--- a/webkit/fileapi/sandbox_mount_point_provider.h
+++ b/webkit/fileapi/sandbox_mount_point_provider.h
@@ -99,6 +99,7 @@
     const GURL& url,
     int64 offset,
     FileSystemContext* context) const OVERRIDE;
+  virtual FileSystemQuotaUtil* GetQuotaUtil() OVERRIDE;
 
   FilePath old_base_path() const;
   FilePath new_base_path() const;
@@ -155,7 +156,6 @@
   virtual void InvalidateUsageCache(const GURL& origin_url,
                                     FileSystemType type) OVERRIDE;
 
-  FileSystemQuotaUtil* quota_util() { return this; }
   void CollectOpenFileSystemMetrics(base::PlatformFileError error_code);
 
  private: