Revert "Removing redundant variables from variance_test.cc."

This reverts commit 4725ab7e.

The constants are necessary to avoid breakage in vs9 builds:
 warning C4180: qualifier applied to function type has no meaning; ignored
 error C2436: 'f2_' : member function or nested class in constructor initializer list
 while compiling class template member function 'std::tr1::tuple<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9>::tuple(const int &,const int &,unsigned int (__cdecl &))'
 ..\test\variance_test.cc : see reference to class template instantiation 'std::tr1::tuple<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9>' being compiled

Change-Id: Ia218b74fc473d40f02fee84cb7009adfbe82e5a7