* it is not necessary, because user could print sequence info
  by ValuePrinter.

* Simplify Evaluator::create logic. Always use ClassRegister to
  create Evaluator.

* It seems some other change breaks the async load. It will cause data
  error in GPU mode.

Change-Id: Ie09fd666ca208994f22e9f83af6072f4d5e6aa1a

* CHECK_XX in glog need the left and right values are both signed or
  unsigned integer. So we could use integer literal syntax in C/C++
  to make literal unsigned or signed. Add suffix 'UL' means unsigned
  long.