Show a warning when the history files can't be read correctly....

chrome/browser/history/history.cc

 // Copyright (c) 2009 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.
 
 // The history system runs on a background thread so that potentially slow
 // database operations don't delay the browser. This backend processing is
 // represented by HistoryBackend. The HistoryService's job is to dispatch to
 // that thread.
 //
 // Main thread                       History thread
@@ skipping 76 matching lines @@
 // separate class from the history service so that it can hold a reference to
 // the history service (otherwise we would have to manually AddRef and
 // Release when the Backend has a reference to us).
 class HistoryService::BackendDelegate : public HistoryBackend::Delegate {
  public:
   explicit BackendDelegate(HistoryService* history_service)
       : history_service_(history_service),
         message_loop_(MessageLoop::current()) {
   }
 
-  virtual void NotifyTooNew() {
+  virtual void NotifyProfileError(int message_id) {
     // Send the backend to the history service on the main thread.
     message_loop_->PostTask(FROM_HERE, NewRunnableMethod(history_service_.get(),
-        &HistoryService::NotifyTooNew));
+        &HistoryService::NotifyProfileError, message_id));
   }
 
   virtual void SetInMemoryBackend(
       history::InMemoryHistoryBackend* backend) {
     // Send the backend to the history service on the main thread.
     message_loop_->PostTask(FROM_HERE, NewRunnableMethod(history_service_.get(),
         &HistoryService::SetInMemoryBackend, backend));
   }
 
   virtual void BroadcastNotifications(NotificationType type,
@@ skipping 548 matching lines @@
 
 void HistoryService::SetInMemoryBackend(
     history::InMemoryHistoryBackend* mem_backend) {
   DCHECK(!in_memory_backend_.get()) << "Setting mem DB twice";
   in_memory_backend_.reset(mem_backend);
 
   // The database requires additional initialization once we own it.
   in_memory_backend_->AttachToHistoryService(profile_);
 }
 
-void HistoryService::NotifyTooNew() {
+void HistoryService::NotifyProfileError(int message_id) {
   Source<HistoryService> source(this);
-  NotificationService::current()->Notify(NotificationType::HISTORY_TOO_NEW,
-      source, NotificationService::NoDetails());
+  NotificationService::current()->Notify(NotificationType::PROFILE_ERROR,
+                                         source, Details<int>(&message_id));
 }
 
 void HistoryService::DeleteURL(const GURL& url) {
   // We will update the visited links when we observe the delete notifications.
   ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::DeleteURL, url);
 }
 
 void HistoryService::ExpireHistoryBetween(
     Time begin_time, Time end_time,
     CancelableRequestConsumerBase* consumer,
@@ skipping 42 matching lines @@
   ScheduleAndForget(PRIORITY_UI, &HistoryBackend::Init);
 }
 
 void HistoryService::OnDBLoaded() {
   LOG(INFO) << "History backend finished loading";
   backend_loaded_ = true;
   NotificationService::current()->Notify(NotificationType::HISTORY_LOADED,
                                          Source<Profile>(profile_),
                                          Details<HistoryService>(this));
 }