[builtins] Remove some (now) unused code from C++ builtin adaptor.

test/mjsunit/es6/symbols.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 508 matching lines @@
   var throwFuncs = [lt, gt, le, ge, lt_same, gt_same, le_same, ge_same];
 
   for (var f of throwFuncs) {
     assertThrows(f, TypeError);
     %OptimizeFunctionOnNextCall(f);
     assertThrows(f, TypeError);
     assertThrows(f, TypeError);
   }
 }
 TestComparison();
+
+
+// Make sure that throws occur in the context of the Symbol function.
+function TestContext() {
+  var r = Realm.create();
+  var rSymbol = Realm.eval(r, "Symbol");
+  var rError = Realm.eval(r, "TypeError");
+
+  function verifier(symbol, error) {
+    try {
+      new symbol();
+    } catch(e) {
+      return e.__proto__ === error.__proto__;
+    }
+    assertTrue(false);  // should never get here.
+  }
+
+  assertTrue(verifier(Symbol, TypeError()));
+  assertTrue(verifier(rSymbol, rError()));
+  assertFalse(verifier(Symbol, rError()));
+  assertFalse(verifier(rSymbol, TypeError()));
+}
+TestContext();