Update CheckBothSmi, CheckInteger32ValidSmiValue, CheckUInteger32ValidSmiValue, SmiAddConstant, SmiNot, AddSmiField and Test to support x32 port.

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/236723004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20862 ce2b1a6d-e550-0410-aec6-3dcde31c8c00