Allow QueryParseException to escape ChangeQueryRewriter

ChangeIndex.getSource throws QueryParseException with the intention of
allowing implementations to not support certain operators/features
(e.g. regex queries). For this to result in a user-visible error
message instead of a 500, we need to not wrap it in an
IllegalStateException.

Change-Id: I8871df8b806cb48ba976ce00f5864a906cd3e9b3
3 files changed