Remove bogus check for TOP register in deoptimizer.

R=danno@chromium.org
BUG=176943

Review URL: https://chromiumcodereview.appspot.com/12300020

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@13690 ce2b1a6d-e550-0410-aec6-3dcde31c8c00