[Nestmates] RFR: 8187360) [Nestmates] Remove invokespecial changes

[David Holmes]

webrev: http://cr.openjdk.java.net/~dholmes/8187360/webrev/

The initial proposal was extending the use of invokespecial to allow it 
to be used for private nestmate method invocations. To support that 
changes had to be made to the verifier. After JVMLS it was decided that 
we would use invokevirtual and invokeinterface (as appropriate) as the 
specification changes needed are much simpler. The switch to that 
approach was done under JDK-8187221 and JDK-8186763. Now we can remove 
the invokespecial changes that were initially put in place.

Thanks,
David