X87:  Make concrete classes for individual call descriptors

port r23639

original commit message:

  Make concrete classes for individual call descriptors. The
  ic-convention classes that hold register specifications are
  merged into these new call descriptor classes, which should
  represent a final home for that information.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/544943002

Patch from Jing Bao <jing.bao@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23708 ce2b1a6d-e550-0410-aec6-3dcde31c8c00