As a first application convert HCompareGeneric to a control Instruction, thus avoid materializing a boolean result value.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/23710070

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16902 ce2b1a6d-e550-0410-aec6-3dcde31c8c00