ES6 symbols: Implement Symbol intrinsic and basic functionality

src/symbol.js

Index: src/symbol.js
diff --git a/test/mjsunit/regress/regress-171641.js b/src/symbol.js
similarity index 86%
copy from test/mjsunit/regress/regress-171641.js
copy to src/symbol.js
index 8db6781821325f8f6253eb2df4abb2b362b001c0..b7f9dc9496aac589e89e2d2761ebe6431a36008e 100644
--- a/test/mjsunit/regress/regress-171641.js
+++ b/src/symbol.js
@@ -25,16 +25,15 @@
 // (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
+"use strict";
 
-function foo(k, p) {
-  for (var i = 0; i < 1; i++) {
-    p = Math.min(p, i);
-  }
-  m = Math.floor((k | 0) / p);
+var $Symbol = function() { return %CreateSymbol() }
+global.Symbol = $Symbol
+
+// Symbols only have a toString method and no prototype.
+var SymbolDelegate = {
+  __proto__: null,
+  toString: $Object.prototype.toString
 }
 
-foo(0, 1);
-foo(0, 1);
-%OptimizeFunctionOnNextCall(foo);
-foo(0, 1);
+$Object.freeze(SymbolDelegate)