[turbofan] Some javascript operators are globally shared singletons.

Also cleanup the interface, and make the parameter class/accessors
explicit to work-around the type-unsafety of OpParameter<T>.

TEST=compiler-unittests,cctest,mjsunit
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/613683002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24322 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Split yet more runtime functions into separate files.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/612383002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24323 ce2b1a6d-e550-0410-aec6-3dcde31c8c00