RFR (S): 8141536, 8141539: Minor java.lang.invoke improvements

[Claes Redestad]

Hi,

looking for reviews for two trivial improvements to java.lang.invoke:

8141536: MethodType field offset calculation could be lazy

  Webrev: http://cr.openjdk.java.net/~redestad/8141536/webrev.01
  Bug: https://bugs.openjdk.java.net/browse/JDK-8141536

8141539: Avoid calculating string constants in InnerClassLambdaMetaFactory

  Webrev: http://cr.openjdk.java.net/~redestad/8141539/webrev.01
  Bug: https://bugs.openjdk.java.net/browse/JDK-8141539

/Claes