Add more per-tab preferences.

chrome/browser/prefs/pref_model_associator.cc

Index: chrome/browser/prefs/pref_model_associator.cc
diff --git a/chrome/browser/prefs/pref_model_associator.cc b/chrome/browser/prefs/pref_model_associator.cc
index 4f06c19b34f01c6ea0c3465da48b9c897166b926..f337ccb657505c063e679194b5080a392feeae2d 100644
--- a/chrome/browser/prefs/pref_model_associator.cc
+++ b/chrome/browser/prefs/pref_model_associator.cc
@@ -376,6 +376,11 @@ 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.