Add more per-tab preferences.

chrome/browser/prefs/pref_model_associator.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/prefs/pref_model_associator.h"
 
 #include "base/auto_reset.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_value_serializer.h"
 #include "base/location.h"
@@ skipping 358 matching lines @@
 
 void PrefModelAssociator::RegisterPref(const char* name) {
   DCHECK(!models_associated_ && registered_preferences_.count(name) == 0);
   registered_preferences_.insert(name);
 }
 
 bool PrefModelAssociator::IsPrefRegistered(const char* name) {
   return registered_preferences_.count(name) > 0;
 }
 
+void PrefModelAssociator::UnregisterPref(const char* name) {
+  CHECK(synced_preferences_.count(name) == 0);

[Bernhard Bauer, 2011/12/28 13:33:42]

Make this a DCHECK? And should this be |registered_preferences_|?

[mnaganov (inactive), 2011/12/28 13:41:40]

Of course, DCHECK. Fixed.

No. If a property isn't contained in registered_preferences_, it means it was
never registered. Thus, it makes no point in unregistering it.
|synced_preferences_| is a set that is filled during preference syncing. The
comment for it says "Note: this set never decreases", so I want to make sure
that unregistering happens before any syncing, as I don't know what will happen
if I violate the "never decreases" assumption by removing a preference from the
set.

[Bernhard Bauer, 2011/12/28 22:35:30]

OK, that makes sense.

+  registered_preferences_.erase(name);
+}
+
 void PrefModelAssociator::ProcessPrefChange(const std::string& name) {
   if (processing_syncer_changes_)
     return;  // These are changes originating from us, ignore.
 
   // We only process changes if we've already associated models.
   if (!models_associated_)
     return;
 
   const PrefService::Preference* preference =
       pref_service_->FindPreference(name.c_str());
@@ skipping 33 matching lines @@
   SyncError error =
       sync_processor_->ProcessSyncChanges(FROM_HERE, changes);
   if (error.IsSet())
     StopSyncing(PREFERENCES);
 }
 
 void PrefModelAssociator::SetPrefService(PrefService* pref_service) {
   DCHECK(pref_service_ == NULL);
   pref_service_ = pref_service;
 }