Fix misplaced assert in heap.cc.

test/mjsunit/bugs/bug-2337.js

Index: test/mjsunit/bugs/bug-2337.js
===================================================================
--- test/mjsunit/bugs/bug-2337.js	(revision 0)
+++ test/mjsunit/bugs/bug-2337.js	(revision 0)
@@ -0,0 +1,53 @@
+// Copyright 2012 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
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (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: --expose-debug-as debug --expose-gc
+
+// If one callback causes a GC then the other callbacks don't take place.
+
+var f = eval("(function f() { return 42; })");
+var f2 = eval("(function f2() { return 43; })");
+
+Debug = debug.Debug;
+
+var called = 0;
+
+function listener(event, exec_state, event_data, data) {
+  if (event == Debug.DebugEvent.ScriptCollected) {
+    if (called != 2) {
+      called++;
+      gc();
+    }
+  }
+};
+
+Debug.scripts();
+Debug.setListener(listener);
+f = void 0;
+f2 = void 0;
+gc();
+assertTrue(called == 2);