When javac 10 and newer are invoked via the API and handle an internal error [1], the crash handling diagnostics are broken, resulting in 'compiler message file broken' instead of the bug parade message.

[1] http://hg.openjdk.java.net/jdk/jdk/file/b7192ab3fdf5/src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTaskImpl.java#l175

The fix is:

- log.printLines("msg.bug", JavaCompiler.version());
+ log.printLines(PrefixKind.JAVAC, "msg.bug", JavaCompiler.version());