syntax fix for GceHost

Use '|' instead of '+' to union sets

TEST=cloud_AccountManager
BUG=b:25291982

Change-Id: I63d8929d61dbb31d0f416308da8a31350cdc4694
Reviewed-on: https://chromium-review.googlesource.com/315736
Commit-Ready: Andrey Ulanov <andreyu@google.com>
Tested-by: Andrey Ulanov <andreyu@google.com>
Reviewed-by: Daniel Wang <wonderfly@google.com>
1 file changed