When constructing stack traces we interpret the deoptimization data for
optimized frames to find the receiver value.  This value could sometimes be
eliminated from the deoptimization data if we though it was unused.

BUG=v8:1118

Review URL: http://codereview.chromium.org/6465023

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6694 ce2b1a6d-e550-0410-aec6-3dcde31c8c00