wait for boot_id in full_power_off_and_on.

- This change is to address firmware_ConsecutiveBoot test failure
  with ConnectionError.  Without this change, the call to
  wait_for_client_offline will timeout after 60 seconds and throw
  ConnectionError exception.

BUG=None
TEST=None

Change-Id: I61dec99adf8fec7a931f85647d60ffad8cae2be6
Reviewed-on: https://chromium-review.googlesource.com/228194
Tested-by: danny chan <dchan@chromium.org>
Reviewed-by: Yusuf Mohsinally <mohsinally@chromium.org>
Commit-Queue: danny chan <dchan@chromium.org>
diff --git a/server/cros/faft/firmware_test.py b/server/cros/faft/firmware_test.py
index 6b541f8..583b3c9 100644
--- a/server/cros/faft/firmware_test.py
+++ b/server/cros/faft/firmware_test.py
@@ -1256,10 +1256,13 @@
 
     def full_power_off_and_on(self):
         """Shutdown the device by pressing power button and power on again."""
+        boot_id = self.get_bootid()
         # Press power button to trigger Chrome OS normal shutdown process.
         # We use a customized delay since the normal-press 1.2s is not enough.
         self.servo.power_key(self.faft_config.hold_pwr_button)
-        self.wait_for_client_offline()
+        # device can take 44-51 seconds to restart,
+        # add buffer from the default timeout of 60 seconds.
+        self.wait_for_client_offline(timeout=100, orig_boot_id=boot_id)
         time.sleep(self.faft_config.shutdown)
         # Short press power button to boot DUT again.
         self.servo.power_short_press()