fixed WithType unification in pattern matching if the type is unknown

git-svn-id: http://haxe.googlecode.com/svn/trunk@6217 f16182fa-f095-11de-8f43-4547254af6c6
do not memq the cloned field (fixed issue #1493)

git-svn-id: http://haxe.googlecode.com/svn/trunk@6218 f16182fa-f095-11de-8f43-4547254af6c6