Revert "Implement handling of arrow functions in the parser"

This reverts revision 22320.

Reason: ASAN still detects leaks!

Conflicts:
	src/preparser.h

TBR=aperez@igalia.com,marja@chromium.org
BUG=

Review URL: https://codereview.chromium.org/389503002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22337 ce2b1a6d-e550-0410-aec6-3dcde31c8c00