removed inappropriate assertion that prevents static method calls

org.springframework.core/src/main/java/org/springframework/util/ReflectionUtils.java

@@ -193,9 +193,6 @@ public abstract class ReflectionUtils {
 	 * @return the invocation result, if any
 	 */
 	public static Object invokeMethod(Method method, Object target, Object... args) {
-		if (target == null) {
-			throw new IllegalArgumentException("target cannot be null");
-		}
 		try {
 			return method.invoke(target, args);
 		}