Fix corner case when transforming dictionary to fast elements.

test/mjsunit/regress-2249.js

Index: test/mjsunit/regress-2249.js
diff --git a/test/mjsunit/regress/regress-2153.js b/test/mjsunit/regress-2249.js
similarity index 93%
copy from test/mjsunit/regress/regress-2153.js
copy to test/mjsunit/regress-2249.js
index 3170042bedc6e80f9ca11436f7162c209eb8f799..5478eb9663061328d9ccdebc59cdd3186f57535d 100644
--- a/test/mjsunit/regress/regress-2153.js
+++ b/test/mjsunit/regress-2249.js
@@ -25,8 +25,10 @@
 // (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: --gc-interval=10 --stress-compaction
+
 var o = {};
-o.__defineGetter__('foo', function () { return null; });
-var o = {};
-o.foo = 42;
-assertEquals(42, o.foo);
+o[Math.pow(2,30)-1] = 0;
+o[Math.pow(2,31)-1] = 0;
+o[1] = 0;
+