Send a TrackedPreference incident when registry pref validation fails.

components/user_prefs/tracked/pref_hash_store_transaction.h

 // Copyright 2014 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 COMPONENTS_USER_PREFS_TRACKED_PREF_HASH_STORE_TRANSACTION_H_
 #define COMPONENTS_USER_PREFS_TRACKED_PREF_HASH_STORE_TRANSACTION_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 20 matching lines @@
     CHANGED,
     // No stored hash exists for the preference value.
     UNTRUSTED_UNKNOWN_VALUE,
     // No stored hash exists for the preference value, but the current set of
     // hashes stored is trusted and thus this value can safely be seeded. This
     // happens when all hashes are already properly seeded and a newly
     // tracked value needs to be seeded).
     TRUSTED_UNKNOWN_VALUE,
     // NULL values are inherently trusted.
     TRUSTED_NULL_VALUE,
+    // This transaction's store type is not supported.
+    UNSUPPORTED,
   };
 
   // Finalizes any remaining work after the transaction has been performed.
   virtual ~PrefHashStoreTransaction() {}
 
   // Returns the suffix to be appended to UMA histograms for the store contained
   // in this transaction.
   virtual base::StringPiece GetStoreUMASuffix() const = 0;
 
   // Checks |initial_value| against the existing stored value hash.
@@ skipping 40 matching lines @@
   // Indicates whether the super MAC was successfully verified at the beginning
   // of this transaction.
   virtual bool IsSuperMACValid() const = 0;
 
   // Forces a valid super MAC to be stored when this transaction terminates.
   // Returns true if this results in a change to the store contents.
   virtual bool StampSuperMac() = 0;
 };
 
 #endif  // COMPONENTS_USER_PREFS_TRACKED_PREF_HASH_STORE_TRANSACTION_H_