[SyncFS] Make GetOriginStatusMap asynchronous

chrome/browser/sync_file_system/remote_file_sync_service.h

Index: chrome/browser/sync_file_system/remote_file_sync_service.h
diff --git a/chrome/browser/sync_file_system/remote_file_sync_service.h b/chrome/browser/sync_file_system/remote_file_sync_service.h
index 8a310548f4c6f122c828809ab80bb3c360d5913d..f2f4ea2559d923efd808196753123fc175c59ac2 100644
--- a/chrome/browser/sync_file_system/remote_file_sync_service.h
+++ b/chrome/browser/sync_file_system/remote_file_sync_service.h
@@ -11,6 +11,7 @@
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
 #include "chrome/browser/sync_file_system/conflict_resolution_policy.h"
 #include "chrome/browser/sync_file_system/sync_callbacks.h"
 #include "chrome/browser/sync_file_system/sync_file_metadata.h"
@@ -111,6 +112,8 @@ class RemoteFileSyncService {
 
   // For GetOriginStatusMap.
   typedef std::map<GURL, std::string> OriginStatusMap;
+  typedef base::Callback<void(scoped_ptr<OriginStatusMap> status_map)>
+      StatusMapCallback;
 
   // For GetRemoteVersions.
   typedef base::Callback<void(SyncStatusCode status,
@@ -192,7 +195,7 @@ class RemoteFileSyncService {
 
   // Returns all origins along with an arbitrary string description of their
   // corresponding sync statuses.
-  virtual void GetOriginStatusMap(OriginStatusMap* status_map) = 0;
+  virtual void GetOriginStatusMap(const StatusMapCallback& callback) = 0;
 
   // Returns file metadata for |origin| to call |callback|.
   virtual void DumpFiles(const GURL& origin,