Merge pull request jruby#9215 from headius/data_new_empty_kwrest

Ignore empty kwrest in Data subtypes' constructors

Author: headius

core/src/main/java/org/jruby/RubyData.java

@@ -40,6 +40,7 @@
 import static org.jruby.runtime.Arity.checkArgumentCount;
 import static org.jruby.runtime.Helpers.invokedynamic;
 import static org.jruby.runtime.ThreadContext.CALL_KEYWORD;
+import static org.jruby.runtime.ThreadContext.CALL_KEYWORD_EMPTY;
 import static org.jruby.runtime.ThreadContext.clearCallInfo;
 import static org.jruby.runtime.ThreadContext.hasKeywords;
 import static org.jruby.runtime.ThreadContext.resetCallInfo;
@@ -309,7 +310,7 @@ public static IRubyObject rbNew(ThreadContext context, IRubyObject self, IRubyOb
 
             RubyHash init;
             int callInfo = resetCallInfo(context);
-            if (hasKeywords(callInfo)) {
+            if (hasKeywords(callInfo) && (callInfo & CALL_KEYWORD_EMPTY) == 0) {
                 if (!(hashOrElt instanceof RubyHash)) {
                     throw argumentError(context, 1, 0, 0);
                 }