This proved to be a fragile technique, which probably doesn't even improve
performance in most cases but has lots of unexpected problems: unconditional
initialization of reflection classes, increasing the size of the bytecode, bugs
with <clinit> in annotations on JVM 6, inability to support conversion of a
class from Kotlin to Java without recompiling clients which use it
reflectively, etc.
Otherwise some tools break (e.g. CheckMethodAdapter in ASM, used in generic
signature writer) because they expect class names to be Java identifiers.
Some tests fixed, some will be fixed in future commits
Dmitry Petrov