Use LookupIterator (and rewrite) DebugLookupResultValue and clients

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/468943002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23201 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Get rid of LookupRealNamedProperty and LookupRealNamedPropertyInPrototypes and update clients

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/481043002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23202 ce2b1a6d-e550-0410-aec6-3dcde31c8c00