This preserves side effects from stores in HCapturedObject markers so
that simulates following these markers are not merged away.

R=titzer@chromium.org
TEST=mjsunit/compiler/escape-analysis --deopt-every-n-times [3,6,9]

Review URL: https://codereview.chromium.org/23554003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16394 ce2b1a6d-e550-0410-aec6-3dcde31c8c00