Split PrefService into PrefService, PrefServiceSimple and PrefServiceSyncable.

chrome/browser/external_protocol/external_protocol_handler.h

Index: chrome/browser/external_protocol/external_protocol_handler.h
diff --git a/chrome/browser/external_protocol/external_protocol_handler.h b/chrome/browser/external_protocol/external_protocol_handler.h
index 2cab580e60dcc8141731b09ddb771c421ec218c7..ae61f926e85be56544a104a7dc3c7dd601faeee9 100644
--- a/chrome/browser/external_protocol/external_protocol_handler.h
+++ b/chrome/browser/external_protocol/external_protocol_handler.h
@@ -10,7 +10,7 @@
 #include "chrome/browser/shell_integration.h"
 
 class GURL;
-class PrefService;
+class PrefServiceSimple;
 
 namespace base {
 class DictionaryValue;
@@ -78,7 +78,7 @@ class ExternalProtocolHandler {
                                         int routing_id);
 
   // Register the ExcludedSchemes preference.
-  static void RegisterPrefs(PrefService* prefs);
+  static void RegisterPrefs(PrefServiceSimple* prefs);
 
   // Starts a url using the external protocol handler with the help
   // of shellexecute. Should only be called if the protocol is whitelisted