Mitigation of Scala reflection bugs (Symbols#CyclicReference, RuntimeException("scala signature"), ...)

[cerveada]

Various Scala bugs may be a cause of failed reflection call:

• Scala reflection: scala.reflect.internal.Symbols$CyclicReference: illegal cyclic reference involving class X scala/bug#12190
• ReflectionUtils: error reading Scala signature #80
• ReflectionUtils: java.lang.AssertionError: assertion failed: unsafe symbol ... (child of <none>) in runtime reflection universe #82

We should try to isolate the user from those bugs. It is a question how to do this, but we should make it clear when there is an actual error and when the cause of the issue was a bug in Scala.