* Eliminate Conditional::then/else_position and WhileStatement::condition_position.

R=yangguo@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23597037

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17184 ce2b1a6d-e550-0410-aec6-3dcde31c8c00