Rather than allocating a fresh gap move resolver for every parallel
move, use a single one per Lithium code generator.  This avoids always
reallocating the temporary zone-allocated lists used by the gap move
resolver.

Review URL: http://codereview.chromium.org/6128007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6270 ce2b1a6d-e550-0410-aec6-3dcde31c8c00