Allow whitelisted prefs to be displayed in ChromeOS in chrome://local-state.

components/prefs/pref_service.h

Index: components/prefs/pref_service.h
diff --git a/components/prefs/pref_service.h b/components/prefs/pref_service.h
index 6c95b64f6536eb1e8174bb097bda4b71bfa31099..9fee491a1a556afde5a89faa8a43c0b588c63743 100644
--- a/components/prefs/pref_service.h
+++ b/components/prefs/pref_service.h
@@ -257,6 +257,11 @@ class COMPONENTS_PREFS_EXPORT PrefService : public base::NonThreadSafe {
   // are at their default values.
   scoped_ptr<base::DictionaryValue> GetPreferenceValuesOmitDefaults() const;
 
+  // Same as GetPreferenceValuesOmitDefaults, but also filters out preferences
+  // keys that do not match one of the prefixes in |whitelisted_prefixes|.
+  scoped_ptr<base::DictionaryValue> GetWhitelistedPreferenceValuesOmitDefaults(
+      const std::vector<std::string>& whitelisted_prefixes) const;
+
   // Returns a dictionary with effective preference values. Contrary to
   // GetPreferenceValues(), the paths of registered preferences are not split on
   // '.' characters. If a registered preference stores a dictionary, however,
@@ -348,6 +353,11 @@ class COMPONENTS_PREFS_EXPORT PrefService : public base::NonThreadSafe {
   virtual void AddPrefObserver(const std::string& path, PrefObserver* obs);
   virtual void RemovePrefObserver(const std::string& path, PrefObserver* obs);
 
+  // Helper function that adds a preference value to a dictionary if it is not
+  // at its default value.
+  void SetPreferenceOmitdefault(const std::string& pref_name,
+                                base::DictionaryValue* out) const;
+
   // Sends notification of a changed preference. This needs to be called by
   // a ScopedUserPrefUpdate if a DictionaryValue or ListValue is changed.
   void ReportUserPrefChanged(const std::string& key);