The constructor check should return false for arrow and generator functions (#4328)

The previous `ecma_is_constructor` implementation did not checked if the
target function was an arrow or generator function. This resulted in
an incorrect execution for these function types.

JerryScript-DCO-1.0-Signed-off-by: Peter Gal pgal.usz@partner.samsung.com

jerry-core/ecma/operations/ecma-function-object.h

@@ -37,6 +37,16 @@ bool ecma_op_object_is_callable (ecma_object_t *obj_p);
 bool ecma_is_constructor (ecma_value_t value);
 bool ecma_object_is_constructor (ecma_object_t *obj_p);
 
+/**
+ * Special constant indicating that the value is a valid constructor
+ *
+ * Use after the ecma_*_check_constructor calls.
+ */
+#define ECMA_IS_VALID_CONSTRUCTOR ((char *) 0x1)
+
+char *ecma_object_check_constructor (ecma_object_t *obj_p);
+char *ecma_check_constructor (ecma_value_t value);
+
 ecma_object_t *
 ecma_op_create_simple_function_object (ecma_object_t *scope_p, const ecma_compiled_code_t *bytecode_data_p);
 
@@ -72,9 +82,6 @@ void
 ecma_op_native_handler_list_lazy_property_names (ecma_object_t *object_p,
                                                  ecma_collection_t *prop_names_p,
                                                  ecma_property_counter_t *prop_counter_p);
-
-bool
-ecma_op_function_is_generator (ecma_object_t *func_obj_p);
 #endif /* ENABLED (JERRY_ESNEXT) */
 
 ecma_object_t *