Fix invalid reuse of weak global handle in GetScriptWrapper.

test/mjsunit/regress/regress-2988.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
 //       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: --allow-natives-syntax
+// Flags: --allow-natives-syntax --gc-global --throws
 
-var c = { x: 2, y: 1 };
+var f = eval("(function f() { throw 'kaboom'; })");
 
-function h() {
-  %MigrateInstance(c);
-  return 2;
-}
-%NeverOptimizeFunction(h);
+// Prepare that next MessageHandler::MakeMessageObject will result in
+// reclamation of existing script wrapper while weak handle is used.
+%FunctionGetScript(f);
+%SetAllocationTimeout(1000, 2);
 
-function f() {
-  for (var i = 0; i < 100000; i++) {
-    var n = c.x + h();
-    assertEquals(4, n);
-  }
-  var o2 = [{ x: 2.5, y:1 }];
-  return o2;
-}
-
+// This call throws to the console but the --throws flag passed to this
+// test will make sure we don't count it as an actual failure.
 f();
-