Eliminate dominator and retained_size fields. They are calculating on front-end side. See meta-bug https://bugs.webkit.org/show_bug.cgi?id=87089

BUG=none
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10416035

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11626 ce2b1a6d-e550-0410-aec6-3dcde31c8c00