Add enable-sync-directory-operation to about:flags

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 8dbe0998b35bb029b825caf33fe3101211a8c702..f408d96b3d09e6cd3b7c0e2b67a7b9174998255c 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -33,6 +33,7 @@
 #include "ui/gl/gl_switches.h"
 #include "ui/keyboard/keyboard_switches.h"
 #include "ui/surface/surface_switches.h"
+#include "webkit/fileapi/syncable/syncable_file_system_util.h"
 
 #if defined(ENABLE_MESSAGE_CENTER)
 #include "ui/message_center/message_center_switches.h"
@@ -1460,6 +1461,14 @@ const Experiment kExperiments[] = {
     kOsWin,
     SINGLE_VALUE_TYPE(switches::kAppsUseNativeFrame)
   },
+  {
+    "enable-sync-directory-operation",
+    IDS_FLAGS_ENABLE_SYNC_DIRECTORY_OPERATION_NAME,
+    IDS_FLAGS_ENABLE_SYNC_DIRECTORY_OPERATION_DESCRIPTION,
+    kOsAll,
+    SINGLE_VALUE_TYPE(
+        sync_file_system::GetFlagForSyncFileSystemDirectoryOperation())
+  },
 };
 
 const Experiment* experiments = kExperiments;