Introduce incognito preference settings.

chrome/browser/prefs/pref_service.cc

Index: chrome/browser/prefs/pref_service.cc
diff --git a/chrome/browser/prefs/pref_service.cc b/chrome/browser/prefs/pref_service.cc
index 4a3110c5c801990e3b5a76d547a588a2cfa62885..6f87b8983872e3da37984eb465d04cc15aa82acd 100644
--- a/chrome/browser/prefs/pref_service.cc
+++ b/chrome/browser/prefs/pref_service.cc
@@ -21,9 +21,11 @@
 #include "base/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_thread.h"
+#include "chrome/browser/extensions/extension_pref_store.h"
 #include "chrome/browser/policy/configuration_policy_pref_store.h"
 #include "chrome/browser/prefs/command_line_pref_store.h"
 #include "chrome/browser/prefs/default_pref_store.h"
+#include "chrome/browser/prefs/overlay_persistent_pref_store.h"
 #include "chrome/browser/prefs/pref_notifier_impl.h"
 #include "chrome/browser/prefs/pref_value_store.h"
 #include "chrome/browser/profiles/profile.h"
@@ -85,9 +87,10 @@ void NotifyReadError(PrefService* pref, int message_id) {
 }  // namespace
 
 // static
-PrefService* PrefService::CreatePrefService(const FilePath& pref_filename,
-                                            PrefStore* extension_prefs,
-                                            Profile* profile) {
+PrefService* PrefService::CreatePrefService(
+    const FilePath& pref_filename,
+    scoped_refptr<PrefStore> extension_prefs,
+    Profile* profile) {
   using policy::ConfigurationPolicyPrefStore;
 
 #if defined(OS_LINUX)
@@ -103,29 +106,52 @@ PrefService* PrefService::CreatePrefService(const FilePath& pref_filename,
   }
 #endif
 
-  ConfigurationPolicyPrefStore* managed =
+  scoped_refptr<ConfigurationPolicyPrefStore> managed =

[Mattias Nissler (ping if slow), 2010/12/20 14:50:02]

scoped_refptr construction not needed here either. Maybe it's time to just
inline the construction below in the constructor call.

[battre, 2010/12/21 18:51:59]

Done.

       ConfigurationPolicyPrefStore::CreateManagedPlatformPolicyPrefStore();
-  ConfigurationPolicyPrefStore* device_management =
+  scoped_refptr<ConfigurationPolicyPrefStore> device_management =
       ConfigurationPolicyPrefStore::CreateDeviceManagementPolicyPrefStore(
           profile);
-  CommandLinePrefStore* command_line =
+  scoped_refptr<CommandLinePrefStore> command_line =
       new CommandLinePrefStore(CommandLine::ForCurrentProcess());
-  JsonPrefStore* user = new JsonPrefStore(
+  scoped_refptr<JsonPrefStore> user = new JsonPrefStore(
       pref_filename,
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
-  ConfigurationPolicyPrefStore* recommended =
+  scoped_refptr<ConfigurationPolicyPrefStore> recommended =
       ConfigurationPolicyPrefStore::CreateRecommendedPolicyPrefStore();
 
   return new PrefService(managed, device_management, extension_prefs,
                          command_line, user, recommended, profile);
 }
 
-PrefService::PrefService(PrefStore* managed_platform_prefs,
-                         PrefStore* device_management_prefs,
-                         PrefStore* extension_prefs,
-                         PrefStore* command_line_prefs,
-                         PersistentPrefStore* user_prefs,
-                         PrefStore* recommended_prefs,
+PrefService* PrefService::CreateIncognitoPrefService(
+    scoped_refptr<PrefStore> incognito_extension_prefs) {
+  return new PrefService(pref_value_store_,
+                         user_pref_store_,
+                         incognito_extension_prefs,
+                         default_store_);
+}
+
+PrefService::PrefService(PrefValueStore* old_pref_value_store,
+                         scoped_refptr<PersistentPrefStore> old_user_pref_store,
+                         scoped_refptr<PrefStore> incognito_extension_prefs,
+                         scoped_refptr<DefaultPrefStore> default_store)
+    : user_pref_store_(new OverlayPersistentPrefStore(old_user_pref_store)),
+      default_store_(default_store) {
+  pref_notifier_.reset(new PrefNotifierImpl(this));
+  pref_value_store_ =
+      old_pref_value_store->Derive(incognito_extension_prefs,
+                                   user_pref_store_,
+                                   pref_notifier_.get());
+  // We do not call InitFromStorage() here intentionally, as we do not read
+  // the user prefs from disk.
+}
+
+PrefService::PrefService(scoped_refptr<PrefStore> managed_platform_prefs,
+                         scoped_refptr<PrefStore> device_management_prefs,
+                         scoped_refptr<PrefStore> extension_prefs,
+                         scoped_refptr<PrefStore> command_line_prefs,
+                         scoped_refptr<PersistentPrefStore> user_prefs,
+                         scoped_refptr<PrefStore> recommended_prefs,
                          Profile* profile)
     : user_pref_store_(user_prefs) {
   pref_notifier_.reset(new PrefNotifierImpl(this));
@@ -328,15 +354,23 @@ FilePath PrefService::GetFilePath(const char* path) const {
 }
 
 bool PrefService::HasPrefPath(const char* path) const {
-  return pref_value_store_->HasPrefPath(path);
+  const Preference* pref = FindPreference(path);
+  return pref && !pref->IsDefaultValue();
 }
 
 const PrefService::Preference* PrefService::FindPreference(
     const char* pref_name) const {
   DCHECK(CalledOnValidThread());
-  Preference p(this, pref_name);
+  Preference p(this, pref_name, Value::TYPE_NULL);
   PreferenceSet::const_iterator it = prefs_.find(&p);
-  return it == prefs_.end() ? NULL : *it;
+  if (it != prefs_.end())
+    return *it;
+  const Value::ValueType type = default_store_->GetType(pref_name);
+  if (type == Value::TYPE_NULL)
+    return NULL;
+  Preference* new_pref = new Preference(this, pref_name, type);
+  prefs_.insert(new_pref);
+  return new_pref;
 }
 
 bool PrefService::ReadOnly() const {
@@ -349,10 +383,7 @@ PrefNotifier* PrefService::pref_notifier() const {
 
 bool PrefService::IsManagedPreference(const char* pref_name) const {
   const Preference* pref = FindPreference(pref_name);
-  if (pref && pref->IsManaged()) {
-    return true;
-  }
-  return false;
+  return pref && pref->IsManaged();
 }
 
 const DictionaryValue* PrefService::GetDictionary(const char* path) const {
@@ -408,18 +439,10 @@ void PrefService::RegisterPreference(const char* path, Value* default_value) {
   DCHECK(orig_type != Value::TYPE_NULL && orig_type != Value::TYPE_BINARY) <<
          "invalid preference type: " << orig_type;
 
-  // We set the default value of dictionaries and lists to be null so it's
-  // easier for callers to check for empty dict/list prefs. The PrefValueStore
-  // accepts ownership of the value (null or default_value).
-  if (Value::TYPE_LIST == orig_type || Value::TYPE_DICTIONARY == orig_type) {
-    default_store_->SetDefaultValue(path, Value::CreateNullValue());
-  } else {
-    // Hand off ownership.
-    default_store_->SetDefaultValue(path, scoped_value.release());
-  }
+  // Hand off ownership.
+  default_store_->SetDefaultValue(path, scoped_value.release());
 
-  pref_value_store_->RegisterPreferenceType(path, orig_type);
-  prefs_.insert(new Preference(this, path));
+  prefs_.insert(new Preference(this, path, orig_type));
 }
 
 void PrefService::ClearPref(const char* path) {
@@ -442,13 +465,7 @@ void PrefService::Set(const char* path, const Value& value) {
     return;
   }
 
-  // Allow dictionary and list types to be set to null, which removes their
-  // user values.
-  if (value.GetType() == Value::TYPE_NULL &&
-      (pref->GetType() == Value::TYPE_DICTIONARY ||
-       pref->GetType() == Value::TYPE_LIST)) {
-    user_pref_store_->RemoveValue(path);
-  } else if (pref->GetType() != value.GetType()) {
+  if (pref->GetType() != value.GetType()) {
     NOTREACHED() << "Trying to set pref " << path
                  << " of type " << pref->GetType()
                  << " to value of type " << value.GetType();
@@ -590,15 +607,17 @@ void PrefService::SetUserPrefValue(const char* path, Value* new_value) {
 // PrefService::Preference
 
 PrefService::Preference::Preference(const PrefService* service,
-                                    const char* name)
+                                    const char* name,
+                                    Value::ValueType type)
       : name_(name),
+        type_(type),
         pref_service_(service) {
   DCHECK(name);
   DCHECK(service);
 }
 
 Value::ValueType PrefService::Preference::GetType() const {
-  return pref_service_->pref_value_store_->GetRegisteredType(name_);
+  return type_;
 }
 
 const Value* PrefService::Preference::GetValue() const {
@@ -606,8 +625,10 @@ const Value* PrefService::Preference::GetValue() const {
       "Must register pref before getting its value";
 
   Value* found_value = NULL;
-  if (pref_service_->pref_value_store_->GetValue(name_, &found_value))
+  if (pref_service_->pref_value_store_->GetValue(name_, type_, &found_value)) {
+    DCHECK(found_value->IsType(type_));
     return found_value;
+  }
 
   // Every registered preference has at least a default value.
   NOTREACHED() << "no valid value found for registered pref " << name_;