Revert "GeneratorFunction() makes generator instances"

test/mjsunit/harmony/generators-iteration.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 306 matching lines @@
         throw (yield (1 + (yield 2) + 3))
       } catch (e) {
         if (typeof e == 'object') throw e;
         return e + (yield (4 + (yield 5) + 6));
       }
     },
     [2, NaN, 5, NaN, NaN],
     "foo",
     [2, "1foo3", 5, "4foo6", "foofoo"]);
 
-// Generator function instances.
-TestGenerator(GeneratorFunction(),
-              [undefined],
-              "foo",
-              [undefined]);
-
-TestGenerator(new GeneratorFunction(),
-              [undefined],
-              "foo",
-              [undefined]);
-
-TestGenerator(GeneratorFunction('yield 1;'),
-              [1, undefined],
-              "foo",
-              [1, undefined]);
-
-TestGenerator(
-    function() { return GeneratorFunction('x', 'y', 'yield x + y;')(1, 2) },
-    [3, undefined],
-    "foo",
-    [3, undefined]);
-
 function TestTryCatch(instantiate) {
   function* g() { yield 1; try { yield 2; } catch (e) { yield e; } yield 3; }
   function Sentinel() {}
 
   function Test1(iter) {
     assertIteratorResult(1, false, iter.next());
     assertIteratorResult(2, false, iter.next());
     assertIteratorResult(3, false, iter.next());
     assertIteratorResult(undefined, true, iter.next());
     assertThrows(function() { iter.next(); }, Error);
@@ skipping 242 matching lines @@
   function TestThrowRecursion() {
     function* g() { yield iter.throw(1); }
     var iter = g();
     return iter.next();
   }
   assertThrows(TestNextRecursion, Error);
   assertThrows(TestSendRecursion, Error);
   assertThrows(TestThrowRecursion, Error);
 }
 TestRecursion();