Fix LoadIC calling convention on ARM

The comments in ic-arm.cc::LoadIC indicated that the receiver should be
both in a register and on the stack.  This isn't true in fact: the code
is careful to spill the receiver if needed.

This CL also fixes up a mistaken use of this convention in in
VisitYield.

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/16203004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15027 ce2b1a6d-e550-0410-aec6-3dcde31c8c00