RFR 8016281: The SAM method should be passed to the metafactory as a MethodType not a MethodHandle

[Robert Field]

Please review the fix for CR:

http://bugs.sun.com/view_bug.do?bug_id=8016281

See also duplicate bug for more motivation:

http://bugs.sun.com/view_bug.do?bug_id=8019635

Webrev:

         http://cr.openjdk.java.net/~rfield/8016281/

Note this includes metafactory (JDK) and the corresponding javac 
(langtools) changes.