network_DisableInterface.pseudomodem: Wait for service to connect first

BUG=chromium:357766
TEST=network_DisableInterface.pseudomodem

Change-Id: I12f04f33680b5df48910702a6fdcf341946d42f5
Reviewed-on: https://chromium-review.googlesource.com/195256
Reviewed-by: Prathmesh Prabhu <pprabhu@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Thieu Le <thieule@chromium.org>
Tested-by: Thieu Le <thieule@chromium.org>
1 file changed