Invalidate embedded objects in optimized code if it was marked for deoptimization.

It avoids having dead pointers in code from the time it was marked for deoptimization until it is deoptimized.

BUG=320532,v8:2996
TEST=mjsunit/regress/regress-320532.js
LOG=Y
R=danno@chromium.org

Review URL: https://chromiumcodereview.appspot.com/61213012

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18013 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce Type::IsCurrently

R=verwaest@chromium.org
BUG=

Review URL: https://codereview.chromium.org/83003003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18015 ce2b1a6d-e550-0410-aec6-3dcde31c8c00