Remove a gratuitous level of indirection in favor of direct calls to the
macro assembler, and eliminate some duplicated code for the uncatchable
case.

R=fschneider@chromium.org
BUG=
TEST=

Review URL: https://chromiumcodereview.appspot.com/9373022

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10671 ce2b1a6d-e550-0410-aec6-3dcde31c8c00