Switch inlining to use simplified instead of machine loads.

R=sigurds@chromium.org
TEST=cctest/test-run-inlining --turbo-types

Review URL: https://codereview.chromium.org/551413002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23813 ce2b1a6d-e550-0410-aec6-3dcde31c8c00