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

[Robert Field]

Please review the UPDATED fix for CR:

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

Changes per two review comments:

         Brian: Restore interface sanity check, but use samBase instead 
of the, now gone, same\Class

         Dan: make the names consistent: metafactory (not metaFactory) 
and altMetafactory (not altMetaFactory)

Webrev:

          http://cr.openjdk.java.net/~rfield/8016281.2/

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