Revert 269415 "Introduce a new framework for back-and-forth trac..."

trunk/src/chrome/browser/prefs/profile_pref_store_manager.cc

Index: trunk/src/chrome/browser/prefs/profile_pref_store_manager.cc
===================================================================
--- trunk/src/chrome/browser/prefs/profile_pref_store_manager.cc	(revision 269437)
+++ trunk/src/chrome/browser/prefs/profile_pref_store_manager.cc	(working copy)
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/prefs/profile_pref_store_manager.h"
 
-#include "base/bind.h"
 #include "base/file_util.h"
 #include "base/json/json_file_value_serializer.h"
 #include "base/logging.h"
@@ -15,7 +14,6 @@
 #include "chrome/browser/prefs/pref_hash_store_impl.h"
 #include "chrome/browser/prefs/tracked/pref_service_hash_store_contents.h"
 #include "chrome/browser/prefs/tracked/segregated_pref_store.h"
-#include "chrome/browser/prefs/tracked/tracked_preferences_migration.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_prefs/pref_registry_syncable.h"
@@ -245,11 +243,24 @@
 
 //  static
 base::Time ProfilePrefStoreManager::GetResetTime(PrefService* pref_service) {
+  // It's a bit of a coincidence that this (and ClearResetTime) work(s). The
+  // PrefHashFilter attached to the protected pref store will store the reset
+  // time directly in the protected pref store without going through the
+  // SegregatedPrefStore.
+
+  // PrefHashFilter::GetResetTime will read the value through the pref service,
+  // and thus through the SegregatedPrefStore. Even though it's not listed as
+  // "protected" it will be read from the protected store preferentially to the
+  // (NULL) value in the unprotected pref store.
   return PrefHashFilter::GetResetTime(pref_service);
 }
 
 // static
 void ProfilePrefStoreManager::ClearResetTime(PrefService* pref_service) {
+  // PrefHashFilter::ClearResetTime will clear the value through the pref
+  // service, and thus through the SegregatedPrefStore. Since it's not listed as
+  // "protected" it will be migrated from the protected store to the unprotected
+  // pref store before being deleted from the latter.
   PrefHashFilter::ClearResetTime(pref_service);
 }
 
@@ -272,7 +283,6 @@
   std::vector<PrefHashFilter::TrackedPreferenceMetadata>
       protected_configuration;
   std::set<std::string> protected_pref_names;
-  std::set<std::string> unprotected_pref_names;
   for (std::vector<PrefHashFilter::TrackedPreferenceMetadata>::const_iterator
            it = tracking_configuration_.begin();
        it != tracking_configuration_.end();
@@ -282,49 +292,41 @@
       protected_pref_names.insert(it->name);
     } else {
       unprotected_configuration.push_back(*it);
-      unprotected_pref_names.insert(it->name);
     }
   }
 
-  scoped_ptr<PrefHashFilter> unprotected_pref_hash_filter(
+  scoped_ptr<PrefFilter> unprotected_pref_hash_filter(
       new PrefHashFilter(GetPrefHashStoreImpl().PassAs<PrefHashStore>(),
                          unprotected_configuration,
                          reporting_ids_count_));
-  scoped_ptr<PrefHashFilter> protected_pref_hash_filter(
+  scoped_ptr<PrefFilter> protected_pref_hash_filter(
       new PrefHashFilter(GetPrefHashStoreImpl().PassAs<PrefHashStore>(),
                          protected_configuration,
                          reporting_ids_count_));
 
-  PrefHashFilter* raw_unprotected_pref_hash_filter =
-      unprotected_pref_hash_filter.get();
-  PrefHashFilter* raw_protected_pref_hash_filter =
-      protected_pref_hash_filter.get();
-
-  scoped_refptr<JsonPrefStore> unprotected_pref_store(
+  scoped_refptr<PersistentPrefStore> unprotected_pref_store(
       new JsonPrefStore(GetPrefFilePathFromProfilePath(profile_path_),
                         io_task_runner,
-                        unprotected_pref_hash_filter.PassAs<PrefFilter>()));
-  scoped_refptr<JsonPrefStore> protected_pref_store(new JsonPrefStore(
+                        unprotected_pref_hash_filter.Pass()));
+  scoped_refptr<PersistentPrefStore> protected_pref_store(new JsonPrefStore(
       profile_path_.Append(chrome::kProtectedPreferencesFilename),
       io_task_runner,
-      protected_pref_hash_filter.PassAs<PrefFilter>()));
+      protected_pref_hash_filter.Pass()));
 
-  SetupTrackedPreferencesMigration(
-      unprotected_pref_names,
+  // The on_initialized callback is used to migrate newly protected values from
+  // the main Preferences store to the Protected Preferences store. It is also
+  // responsible for the initial migration to a two-store model.
+  return new SegregatedPrefStore(
+      unprotected_pref_store,
+      protected_pref_store,
       protected_pref_names,
-      base::Bind(&JsonPrefStore::RemoveValueSilently,
-                 unprotected_pref_store->AsWeakPtr()),
-      base::Bind(&JsonPrefStore::RemoveValueSilently,
-                 protected_pref_store->AsWeakPtr()),
-      base::Bind(&JsonPrefStore::RegisterOnNextSuccessfulWriteCallback,
-                 unprotected_pref_store->AsWeakPtr()),
-      base::Bind(&JsonPrefStore::RegisterOnNextSuccessfulWriteCallback,
-                 protected_pref_store->AsWeakPtr()),
-      raw_unprotected_pref_hash_filter,
-      raw_protected_pref_hash_filter);
-
-  return new SegregatedPrefStore(unprotected_pref_store, protected_pref_store,
-                                 protected_pref_names);
+      base::Bind(&PrefHashFilter::MigrateValues,
+                 base::Owned(new PrefHashFilter(
+                     CopyPrefHashStore(),
+                     protected_configuration,
+                     reporting_ids_count_)),
+                 unprotected_pref_store,
+                 protected_pref_store));
 }
 
 void ProfilePrefStoreManager::UpdateProfileHashStoreIfRequired(
@@ -408,3 +410,15 @@
       scoped_ptr<HashStoreContents>(new PrefServiceHashStoreContents(
           profile_path_.AsUTF8Unsafe(), local_state_))));
 }
+
+scoped_ptr<PrefHashStore> ProfilePrefStoreManager::CopyPrefHashStore() {
+  DCHECK(kPlatformSupportsPreferenceTracking);
+
+  PrefServiceHashStoreContents real_contents(profile_path_.AsUTF8Unsafe(),
+                                             local_state_);
+  return scoped_ptr<PrefHashStore>(new PrefHashStoreImpl(
+      seed_,
+      device_id_,
+      scoped_ptr<HashStoreContents>(
+          new DictionaryHashStoreContents(real_contents))));
+}