tools/jlink/plugins/GenerateJLIClassesPluginTest.java can't compile after JDK-8163371

This has been observed failing on all platforms.
It is because
error: defaultSpecies() has private access in GenerateJLIClassesPlugin
                    classFilesForSpecies(GenerateJLIClassesPlugin.defaultSpecies()),
                                                                 ^
1 error
result: Failed. Compilation failed: Compilation failed

In JDK-8163371, http://hg.openjdk.java.net/jdk9/dev/jdk/rev/a3ba85993930
It changed
- public static List<String> defaultSpecies() {

+ private static List<String> defaultSpecies() {