Refactor sync-specific parts out of SyncNotifier/SyncNotifierObserver

sync/notifier/chrome_invalidation_client.h

Index: sync/notifier/chrome_invalidation_client.h
diff --git a/sync/notifier/chrome_invalidation_client.h b/sync/notifier/chrome_invalidation_client.h
index 6d1c07346799f71df444e644367fa42dd6545216..9841680883b03499c899b52e36c61b6a5907d7c8 100644
--- a/sync/notifier/chrome_invalidation_client.h
+++ b/sync/notifier/chrome_invalidation_client.h
@@ -9,7 +9,6 @@
 #define SYNC_NOTIFIER_CHROME_INVALIDATION_CLIENT_H_
 #pragma once
 
-#include <map>
 #include <string>
 
 #include "base/basictypes.h"
@@ -22,8 +21,8 @@
 #include "sync/internal_api/public/util/weak_handle.h"
 #include "sync/notifier/chrome_system_resources.h"
 #include "sync/notifier/invalidation_state_tracker.h"
-#include "sync/notifier/invalidation_util.h"
 #include "sync/notifier/notifications_disabled_reason.h"
+#include "sync/notifier/object_id_payload_map.h"
 #include "sync/notifier/state_writer.h"
 
 namespace buzz {
@@ -38,10 +37,6 @@ namespace syncer {
 
 class RegistrationManager;
 
-typedef std::map<invalidation::ObjectId,
-                 std::string,
-                 ObjectIdLessThan> ObjectIdPayloadMap;
-
 // ChromeInvalidationClient is not thread-safe and lives on the sync
 // thread.
 class ChromeInvalidationClient