RFR JDK-8215470: Bad EnclosingMethod attribute on classes declared in lambdas

[Vicente Romero]

Please review fix for [1] at [2]. The fix is about pointing the 
enclosing method attribute of inner classes inside a lambda; to the 
original method in which the inner class was declared. Currently javac 
is pointing it to the synthetic method that contains the lambda 
implementation. Please review the CSR too,

Thanks,
Vicente

[1] https://bugs.openjdk.java.net/browse/JDK-8215470
[2] http://cr.openjdk.java.net/~vromero/8215470/webrev.00/
[3] https://bugs.openjdk.java.net/browse/JDK-8217272