SyncFS: Support resolveLocalFileSystemURL on SyncFileSystem

chrome/browser/sync_file_system/local/sync_file_system_backend.cc

Index: chrome/browser/sync_file_system/local/sync_file_system_backend.cc
diff --git a/chrome/browser/sync_file_system/local/sync_file_system_backend.cc b/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
index 1c9eef5d05909c0f75f153f768a7f64bff942902..6de402f4838de7945209d63a6c628af9836f19c8 100644
--- a/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
+++ b/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
@@ -66,6 +66,10 @@ SyncFileSystemBackend::SyncFileSystemBackend(Profile* profile)
   DCHECK(CalledOnUIThread());
   if (profile)
     profile_holder_.reset(new ProfileHolder(profile));
+
+  // Register the service name here to enable to crack an URL on SyncFileSystem
+  // even if SyncFileSystemService has not started yet.
+  RegisterSyncableFileSystem();
 }
 
 SyncFileSystemBackend::~SyncFileSystemBackend() {