Add support for new.target (#3469)

Notable changes:
* Extracted the pure JS/builtin and external C method invocations
  into two new methods (`ecma_op_function_call_{simple, external}`).
* Updated parser/scanner to handle "new.target" correctly.
* Added JS test case.

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

jerry-core/parser/js/js-parser.c

@@ -1982,6 +1982,10 @@ parser_parse_source (const uint8_t *arg_list_p, /**< function argument list */
   {
     context.status_flags |= PARSER_IS_EVAL;
   }
+  if (parse_opts & ECMA_PARSE_FUNCTION)
+  {
+    context.status_flags |= PARSER_IS_FUNCTION;
+  }
 #endif /* ENABLED (JERRY_ES2015) */
 
   scanner_scan_all (&context,