Introduce per-tab preferences service.

chrome/browser/prefs/pref_notifier_impl.cc

Index: chrome/browser/prefs/pref_notifier_impl.cc
diff --git a/chrome/browser/prefs/pref_notifier_impl.cc b/chrome/browser/prefs/pref_notifier_impl.cc
index ec5352bcae54d5b63881271e6887991feafb589e..a01c89f3e525088a32cbff24fb79380b7cd8f69a 100644
--- a/chrome/browser/prefs/pref_notifier_impl.cc
+++ b/chrome/browser/prefs/pref_notifier_impl.cc
@@ -5,13 +5,15 @@
 #include "chrome/browser/prefs/pref_notifier_impl.h"
 
 #include "base/stl_util.h"
+#include "chrome/browser/prefs/pref_model_associator.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_service.h"
 
-PrefNotifierImpl::PrefNotifierImpl(PrefService* service)
-    : pref_service_(service) {
+PrefNotifierImpl::PrefNotifierImpl()
+    : pref_service_(NULL),
+      pref_model_associator_(NULL) {
 }
 
 PrefNotifierImpl::~PrefNotifierImpl() {
@@ -88,9 +90,12 @@ void PrefNotifierImpl::FireObservers(const std::string& path) {
   DCHECK(CalledOnValidThread());
 
   // Only send notifications for registered preferences.
-  if (!pref_service_->FindPreference(path.c_str()))
+  if (!pref_service_ || !pref_service_->FindPreference(path.c_str()))
     return;
 
+  if (pref_model_associator_)
+    pref_model_associator_->ProcessPrefChange(path);

[Mattias Nissler (ping if slow), 2011/11/16 12:08:04]

Seems like this now duplicates the same thing in
PrefValueStore::NotifyPrefChanged(). I'm happy if you move the functionality
here, but then please remove the reference to the associator from
PrefValueStore.

[mnaganov (inactive), 2011/11/17 16:50:58]

Right. I haven't understood that from your change. But it looks like removing an
associator from value store requires cascading changes in tests, so let's do it
as a separate change. For now, I'm not adding an associator into notifier.

+
   const PrefObserverMap::iterator observer_iterator =
       pref_observers_.find(path);
   if (observer_iterator == pref_observers_.end())
@@ -104,3 +109,14 @@ void PrefNotifierImpl::FireObservers(const std::string& path) {
                       content::Details<const std::string>(&path));
   }
 }
+
+void PrefNotifierImpl::SetPrefModelAssociator(
+    PrefModelAssociator* pref_model_associator) {
+  DCHECK(pref_model_associator_ == NULL);
+  pref_model_associator_ = pref_model_associator;
+}
+
+void PrefNotifierImpl::SetPrefService(PrefService* pref_service) {
+  DCHECK(pref_service_ == NULL);
+  pref_service_ = pref_service;
+}