Don't leak visited site information from original profile to OTR profile....

chrome/common/visitedlink_common.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_COMMON_VISITEDLINK_COMMON_H__
 #define CHROME_COMMON_VISITEDLINK_COMMON_H__
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 76 matching lines @@
     uint32 length;
 
     // goes into salt_
     uint8 salt[LINK_SALT_LENGTH];
   };
 
   // Returns the fingerprint at the given index into the URL table. This
   // function should be called instead of accessing the table directly to
   // contain endian issues.
   Fingerprint FingerprintAt(int32 table_offset) const {
-    DCHECK(hash_table_);
     if (!hash_table_)
-      return 0;
+      return null_fingerprint_;
     return hash_table_[table_offset];
   }
 
   // Computes the fingerprint of the given canonical URL. It is static so the
   // same algorithm can be re-used by the table rebuilder, so you will have to
   // pass the salt as a parameter. See the non-static version above if you
   // want to use the current class' salt.
   static Fingerprint ComputeURLFingerprint(const char* canonical_url,
                                            size_t url_len,
                                            const uint8 salt[LINK_SALT_LENGTH]);
 
   // Computes the hash value of the given fingerprint, this is used as a lookup
   // into the hashtable.
   static Hash HashFingerprint(Fingerprint fingerprint, int32 table_length) {
+    if (table_length == 0)
+      return null_hash_;
     return static_cast<Hash>(fingerprint % table_length);
   }
   // Uses the current hashtable.
   Hash HashFingerprint(Fingerprint fingerprint) const {
     return HashFingerprint(fingerprint, table_length_);
   }
 
   // pointer to the first item
   VisitedLinkCommon::Fingerprint* hash_table_;
 
   // the number of items in the hash table
   int32 table_length_;
 
   // salt used for each URL when computing the fingerprint
   uint8 salt_[LINK_SALT_LENGTH];
 
  private:
   DISALLOW_EVIL_CONSTRUCTORS(VisitedLinkCommon);
 };
 
 #endif // WIN_COMMON_VISITEDLINK_COMMON_H__