Move codeRef out of QV4::Function

Change-Id: I65700b9cc4907aaa28623a95204e88f87fccfd49
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Store the file name per compilation unit, not per compiled function

Change-Id: Id699897b241a9ff6495689e5685092d311acb8c2
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Initialize formals and locals from the compiled function data instead of in the isel

Change-Id: I9db976df310a5986ceca66d21efeeae536dbede4
Reviewed-by: Lars Knoll <lars.knoll@digia.com>