Rollback of r13978 in trunk branch.

Move context global handle creation out of Genesis.

TBR=mstarzinger@chromium.org

Review URL: https://chromiumcodereview.appspot.com/12945009

git-svn-id: https://v8.googlecode.com/svn/trunk@13995 ce2b1a6d-e550-0410-aec6-3dcde31c8c00