Implement syncFileSystem.getServiceStatus()

BUG=262824
TEST=FileSystemApiTest.GetServiceStatus

Review URL: https://chromiumcodereview.appspot.com/23623006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@220322 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/extension_function_histogram_value.h b/chrome/browser/extensions/extension_function_histogram_value.h
index 18c03cf..700492833 100644
--- a/chrome/browser/extensions/extension_function_histogram_value.h
+++ b/chrome/browser/extensions/extension_function_histogram_value.h
@@ -614,6 +614,7 @@
   SESSIONS_GETRECENTLYCLOSED,
   SESSIONS_GETDEVICES,
   SESSIONS_RESTORE,
+  SYNCFILESYSTEM_GETSERVICESTATUS,
   ENUM_BOUNDARY // Last entry: Add new entries above.
 };