Remove support for legacy const, part 1

test/mjsunit/regress/regress-88591.js

Index: test/mjsunit/regress/regress-88591.js
diff --git a/test/mjsunit/regress/regress-88591.js b/test/mjsunit/regress/regress-88591.js
index e7f410d7b080a3ac4182076dc86a7b1993a70cce..878e7918b184217c84dca4f0eef718ac92f555eb 100644
--- a/test/mjsunit/regress/regress-88591.js
+++ b/test/mjsunit/regress/regress-88591.js
@@ -25,8 +25,6 @@
 // (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: --legacy-const
-
 // Regression test for a crash.  A data property in the global object's
 // prototype shadowed by a setter in the global object's prototype's
 // prototype would crash or assert when seen by Runtime_DeclareContextSlot.
@@ -36,9 +34,9 @@ Object.prototype.__defineGetter__('x', function () { return 0; });
 
 this.__proto__ = { x: 1 };
 
-try { fail; } catch (e) { eval('const x = 2'); }
+try { fail; } catch (e) { eval('var x = 2'); }
 
 var o = Object.getOwnPropertyDescriptor(this, 'x');
 assertFalse(called);
 assertEquals(2, o.value);
-assertEquals(false, o.writable);
+assertEquals(true, o.writable);