http://mail.openjdk.java.net/pipermail/serviceability-dev/2017-August/021770.html


   - Suggested fix
     http://cr.openjdk.java.net/~ysuenaga/hsdb-fix/conflict-type/

   - How to reproduce
    1. Start JShell
    2. Attach HSDB to jdk.jshell/jdk.internal.jshell.tool.JShellToolProvider
        $ jhsdb hsdb --pid <PID of JShellToolProvider>
    3. Choose "output reader" thread on Java Threads window
    4. Click "Show Java stack trace" icon on "Java Threads" toolbar.

   - Stack trace
```
Exception in thread "AWT-EventQueue-0" sun.jvm.hotspot.utilities.AssertionFailure: type check
at jdk.hotspot.agent/sun.jvm.hotspot.utilities.Assert.that(Assert.java:32)
at jdk.hotspot.agent/sun.jvm.hotspot.runtime.StackValue.getObject(StackValue.java:59)
at jdk.hotspot.agent/sun.jvm.hotspot.runtime.StackValueCollection.oopHandleAt(StackValueCollection.java:51)
at jdk.hotspot.agent/sun.jvm.hotspot.ui.classbrowser.HTMLGenerator.genHTMLForJavaStackTrace(HTMLGenerator.java:1931)
at jdk.hotspot.agent/sun.jvm.hotspot.ui.JavaStackTracePanel.setJavaThread(JavaStackTracePanel.java:78)
at jdk.hotspot.agent/sun.jvm.hotspot.HSDB.showJavaStackTrace(HSDB.java:1526)
```

   I guess it is caused by inlined method which is generated by JIT compiler.
   StackValue has T_CONFLICT value. It might be able to skip.
   I'm not sure about this. So I need comments.