to the runtime will both patch in the more specialized binary op
stub and calculate the answer.  This eliminates the need to call
both the rest of the binary op and the patching runtime call.  The
runtime routines are altered to be more agressive in returning
Smis so we don't get spurious heap numbers as inputs to binary ops
while we are patching the binary op ICs.
Review URL: http://codereview.chromium.org/2843049

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5026 ce2b1a6d-e550-0410-aec6-3dcde31c8c00