Remove several ecma_op_object_get_[own_]property calls.

The ecma_op_object_get_[own_]property calls should be phased out from
the project eventually and virtual properties should be introduced instead.

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

jerry-core/ecma/base/ecma-globals.h

@@ -79,6 +79,7 @@ typedef enum
   ECMA_SIMPLE_VALUE_TRUE, /**< boolean true */
   ECMA_SIMPLE_VALUE_UNDEFINED, /**< undefined value */
   ECMA_SIMPLE_VALUE_NULL, /**< null value */
+  ECMA_SIMPLE_VALUE_NOT_FOUND, /**< a special value returned by ecma_op_object_find */
   ECMA_SIMPLE_VALUE_REGISTER_REF, /**< register reference, a special "base" value for vm */
   ECMA_SIMPLE_VALUE__COUNT /** count of simple ecma values */
 } ecma_simple_value_t;