Fix crasher when checking for "of", but next token has no literal buffer

test/mjsunit/regress/regress-crbug-248025.js

-// Copyright 2012 the V8 project authors. All rights reserved.
+// 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
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 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+// Flags: --harmony-iteration
+
 // Filler long enough to trigger lazy parsing.
 var filler = "//" + new Array(1024).join('x');
 
-var scope = { x:23 };
-
-with(scope) {
-  eval(
-    "scope.f = (function outer() {" +
-    "  function inner() {" +
-    "    return x;" +
-    "  }" +
-    "  return inner;" +
-    "})();" +
-    filler
-  );
-};
-
-assertSame(23, scope.f());
+// Test that the pre-parser does not crash when the expected contextual
+// keyword as part if a 'for' statement is not and identifier.
+try {
+  eval(filler + "\nfunction f() { for (x : y) { } }");
+  throw "not reached";
+} catch (e) {
+  if (!(e instanceof SyntaxError)) throw e;
+}