Static JavaProxy#getJavaClass needs to clear $! #1636
Calls from Ruby which go through the static
(I stumbled on this because Minitest was loading all tests up but then executing none of them because
Calls from Ruby which go through JavaProxy.getJavaClass (ie. field_writer, field_reader, and field_accessor) can result in $! incorrectly containing a NoMethodError from its attempt to invoke "java_class". Ensure we clear it in the catch block.