E.g. make sure that Int32Matcher matches only int32 constants, and
Float64Matcher matches only float64 constants.

Also remove the confusing CommonOperatorTraits, which are too easy
to use in a wrong way.

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

Review URL: https://codereview.chromium.org/552653003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23768 ce2b1a6d-e550-0410-aec6-3dcde31c8c00