Move wait_fw_screen_and_plug_usb() to FAFTSequence base class.

BUG=chromium-os:19710
TEST=run_remote_tests.sh --remote=$REMOTE_IP -a "xml_config=$OVERLAY_XML \
        servo_vid=0x18d1 servo_pid=0x5001" RecoveryButton/control.normal
     run_remote_tests.sh --remote=$REMOTE_IP -a "xml_config=$OVERLAY_XML \
        servo_vid=0x18d1 servo_pid=0x5001" DevTriggerRecovery/control

Change-Id: If54ad1e670f32cd57a9914e0f296f2fc633f97e2
Reviewed-on: https://gerrit.chromium.org/gerrit/12480
Commit-Ready: Tom Wai-Hong Tam <waihong@chromium.org>
Reviewed-by: Tom Wai-Hong Tam <waihong@chromium.org>
Tested-by: Tom Wai-Hong Tam <waihong@chromium.org>
5 files changed