[Nestmates] RFR: 8194856: [Nestmates] Activate nestmate processing for JDK Version 11 only

[David Holmes]

Trivial update:
- javac: only generate nestmate attributes and virtual invoke bytecodes 
for private methods, when outputting for JDK 11 / classfile version 55
- hotspot: only read nestmate attributes if classfile version >= 55 (JDK 11)

bug: https://bugs.openjdk.java.net/browse/JDK-8194856
webrev: http://cr.openjdk.java.net/~dholmes/8194856/webrev/

Thanks,
David
-----

--- old/src/hotspot/share/classfile/classFileParser.cpp	2018-01-14 
22:35:12.386673245 -0500
+++ new/src/hotspot/share/classfile/classFileParser.cpp	2018-01-14 
22:35:10.230549972 -0500
@@ -3469,7 +3469,7 @@
            assert(runtime_invisible_type_annotations != NULL, "null 
invisible type annotations");
          }
          cfs->skip_u1(attribute_length, CHECK);
-      } else if (_major_version >= JAVA_10_VERSION) {
+      } else if (_major_version >= JAVA_11_VERSION) {
          if (tag == vmSymbols::tag_nest_members()) {
            // Check for NestMembers tag
            if (parsed_nest_members_attribute) {
--- 
old/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Target.java 
2018-01-14 22:35:19.063054956 -0500
+++ 
new/src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/Target.java 
2018-01-14 22:35:16.894930997 -0500
@@ -1,5 +1,5 @@
  /*
- * Copyright (c) 2002, 2017, Oracle and/or its affiliates. All rights 
reserved.
+ * Copyright (c) 2002, 2018, Oracle and/or its affiliates. All rights 
reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
@@ -158,13 +158,13 @@
      /** Does the target VM support nestmate access?
       */
      public boolean hasNestmateAccess() {
-        return compareTo(JDK1_10) >= 0;
+        return compareTo(JDK1_11) >= 0;
      }

      /** Does the target VM support virtual private invocations?
       */
      public boolean hasVirtualPrivateInvoke() {
-        return compareTo(JDK1_10) >= 0;
+        return compareTo(JDK1_11) >= 0;
      }

  }