Separate storage for protected preferences into Protected Preferences file.

chrome/browser/prefs/pref_hash_filter.cc

Index: chrome/browser/prefs/pref_hash_filter.cc
diff --git a/chrome/browser/prefs/pref_hash_filter.cc b/chrome/browser/prefs/pref_hash_filter.cc
index b937c358faf770b5f379d1bda8d8698f0f993093..886ec0950e3fcc12bb61ddd733fd519168f426d9 100644
--- a/chrome/browser/prefs/pref_hash_filter.cc
+++ b/chrome/browser/prefs/pref_hash_filter.cc
@@ -8,6 +8,7 @@
 
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
+#include "base/prefs/persistent_pref_store.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/pref_store.h"
 #include "base/strings/string_number_conversions.h"
@@ -91,6 +92,36 @@ void PrefHashFilter::ClearResetTime(PrefService* user_prefs) {
   user_prefs->ClearPref(prefs::kPreferenceResetTime);
 }
 
+void PrefHashFilter::MigrateValues(PersistentPrefStore* source,
+                                   PersistentPrefStore* destination) {
+  scoped_ptr<PrefHashStoreTransaction> transaction =
+      pref_hash_store_->BeginTransaction();
+  for (TrackedPreferencesMap::const_iterator it = tracked_paths_.begin();
+       it != tracked_paths_.end();
+       ++it) {
+    if (!destination->GetValue(it->first, NULL)) {
+      const base::Value* source_value = NULL;
+      base::DictionaryValue temp_dictionary;
+      if (source->GetValue(it->first, &source_value))

[robertshield, 2014/03/25 03:05:12]

if this fails, can we skip the rest of this loop iteration?

[erikwright (departed), 2014/03/25 20:28:26]

No. We want to check if NULL is what was expected, for reporting purposes.

+        temp_dictionary.Set(it->first, source_value->DeepCopy());
+      it->second->EnforceAndReport(&temp_dictionary, transaction.get());

[robertshield, 2014/03/25 03:05:12]

this line needs a comment stating that it validates the setting and can remove
it from the dict if it fails to validate (that isn't clear even from the
documentation on EnforceAndReport).

[erikwright (departed), 2014/03/25 20:28:26]

Done.

+      scoped_ptr<base::Value> checked_value;
+      if (temp_dictionary.Remove(it->first, &checked_value))
+        destination->SetValue(it->first, checked_value.release());
+    }
+    source->RemoveValue(it->first);
+  }
+
+  // Order these such that a crash at any point is still recoverable. We assume
+  // that they are configured such that the writes will occur on worker threads
+  // in the order that we asked for them.
+  destination->CommitPendingWrite();
+  transaction.reset();
+  // If we crash here, we will just delete the values from |source| in a future
+  // run.

[robertshield, 2014/03/25 03:05:12]

".. in a future run when MigrateValues() is called again."

[erikwright (departed), 2014/03/25 20:28:26]

Done.

+  source->CommitPendingWrite();
+}
+
 void PrefHashFilter::Initialize(const PrefStore& pref_store) {
   scoped_ptr<PrefHashStoreTransaction> hash_store_transaction(
       pref_hash_store_->BeginTransaction());