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

Also fix a typo in an assertion in scanner.h.

R=mstarzinger@chromium.org
BUG=248025
TEST=mjsunit/regress/regress-crbug-248025.js

Review URL: https://codereview.chromium.org/16549003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15059 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/preparser.cc

@@ -662,6 +662,7 @@ PreParser::Statement PreParser::ParseWhileStatement(bool* ok) {
 bool PreParser::CheckInOrOf() {
   if (peek() == i::Token::IN ||
       (allow_for_of() &&
+       peek() == i::Token::IDENTIFIER &&
        scanner_->is_next_contextual_keyword(v8::internal::CStrVector("of")))) {
     Next();
     return true;

src/scanner.h

@@ -331,7 +331,7 @@ class Scanner {
     return current_.literal_chars->is_ascii();
   }
   bool is_literal_contextual_keyword(Vector<const char> keyword) {
-    ASSERT_NOT_NULL(next_.literal_chars);
+    ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->is_contextual_keyword(keyword);
   }
   int literal_length() const {

test/mjsunit/regress/regress-crbug-248025.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: --harmony-iteration
+
+// Filler long enough to trigger lazy parsing.
+var filler = "//" + new Array(1024).join('x');
+
+// 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;
+}