Make stray 'return' an early error

test/mjsunit/debug-stepout-scope-part4.js

 // Copyright 2011 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 37 matching lines @@
       exec_state.prepareStep(Debug.StepAction.StepInMin, 1);
     }
   }
 }
 
 Debug.setListener(listener);
 
 var q = 42;
 var prefixes = [
   "debugger; ",
-  "if (false) { try { throw 0; } catch(x) { return x; } }; debugger; " ];
+  "if (false) { try { throw 0; } catch(x) { this.x = x; } }; debugger; " ];
 var bodies = [ "1",
                "1 ",
                "1;",
                "1; ",
                "q",
                "q ",
                "q;",
                "q; ",
                "try { throw 'stuff' } catch (e) { e = 1; }",
                "try { throw 'stuff' } catch (e) { e = 1; } ",
                "try { throw 'stuff' } catch (e) { e = 1; };",
                "try { throw 'stuff' } catch (e) { e = 1; }; " ];
 
 
 // Test global eval and function constructor.
 for (var i = 0; i < prefixes.length; ++i) {
   var pre = prefixes[i];
   for (var j = 0; j < bodies.length; ++j) {
     var body = bodies[j];
     eval(pre + body);
   }
 }