Port r9543 to the 3.4 branch.

test/mjsunit/regress/regress-1521.js

Index: test/mjsunit/regress/regress-1521.js
diff --git a/test/mjsunit/regress/regress-1521.js b/test/mjsunit/regress/regress-1521.js
index 415db6780324621d59ff4efdb30da66706aa596d..3149f05a5e93e6711561d4eec4d7c84aa80edcbc 100644
--- a/test/mjsunit/regress/regress-1521.js
+++ b/test/mjsunit/regress/regress-1521.js
@@ -24,6 +24,8 @@
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Flags: --allow-natives-syntax
 
 // Optimized variable access inside through a catch context should work.
 function test(x) {
@@ -44,4 +46,3 @@ function test(x) {
 }
 
 test(3);
-