RFR: 8198755: Reduce cost of InvokerBytecodeGenerator::isStaticallyInvocable/-Nameable

[Claes Redestad]

Hi,

when generating LF classes with InvokerBytecodeGenerator, almost 5% of 
executed code is concerned with determining if members and parameters 
are statically invocable and/or nameable, which we can assert is always 
true for MethodHandle arguments.

Since MethodHandle targets and parameters are common, it's a profitable 
startup optimization to add a fast-path test for this.

Webrev: http://cr.openjdk.java.net/~redestad/8198755/jdk.00/
Bug: https://bugs.openjdk.java.net/browse/JDK-8198755

Thanks!

/Claes