Also make internal API generate Java 9 compatible (new version numbers)

src/main/resources/de/thetaphi/forbiddenapis/signatures/jdk-internal-1.9.txt

@@ -2,7 +2,7 @@
 # It is provided here for reference, but can easily regenerated by executing from the source folder of forbidden-apis:
 # $ ant generate-internal
 
-# This file contains all internal packages listed in Security.getProperty("package.access") of Java version 1.9 (extracted from build 1.9.0-ea).
+# This file contains all internal packages listed in Security.getProperty("package.access") of Java version 1.9 (extracted from build 9-ea).
 
 @defaultMessage non-public internal runtime class in Java 1.9
 
@@ -37,6 +37,7 @@ com.sun.org.apache.xalan.internal.xsltc.util.**
 com.sun.org.apache.xerces.internal.**
 com.sun.org.apache.xml.internal.res.**
 com.sun.org.apache.xml.internal.security.**
+com.sun.org.apache.xml.internal.serializer.dom3.**
 com.sun.org.apache.xml.internal.serializer.utils.**
 com.sun.org.apache.xml.internal.utils.**
 com.sun.org.apache.xpath.internal.**
@@ -53,6 +54,7 @@ jdk.internal.**
 jdk.management.cmm.internal.**
 jdk.nashorn.internal.**
 jdk.nashorn.tools.**
+jdk.rmi.rmic.**
 jdk.tools.jimage.**
 oracle.jrockit.jfr.**
 org.jcp.xml.dsig.internal.**

src/tools/java/de/thetaphi/forbiddenapis/InternalApiGen.java

@@ -41,8 +41,6 @@ public final class InternalApiGen {
   InternalApiGen(String javaVersion, File output) {
     this.javaVersion = javaVersion;
     this.output = output;
-    if (!System.getProperty("java.version").startsWith(javaVersion))
-      throw new IllegalArgumentException("Java version mismatch: build " + System.getProperty("java.version") + " != expected " + javaVersion);
     this.header = new StringBuilder()
       .append("# This file contains API signatures that are marked as internal in Java.").append(NL)
       .append("# It is provided here for reference, but can easily regenerated by executing from the source folder of forbidden-apis:").append(NL)