Trigger lightbar pattern from charger task if necessary

If we have a lightbar, but no PD, then plugging the device in will
not trigger the battery-level pattern. This allows us to trigger
it from the charger task instead if we change AC status and don't
have a PD.

BRANCH=ToT
BUG=None
TEST=plug and unplug charger from device, make sure the lightbar
  plays the right pattern

Change-Id: I8f37aaff2ddb9d936e13489cb404caee822418a1
Signed-off-by: Eric Caruso <ejcaruso@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/292943
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

common/charge_state_v2.c

@@ -16,6 +16,7 @@
 #include "gpio.h"
 #include "hooks.h"
 #include "host_command.h"
+#include "lightbar.h"
 #include "math_util.h"
 #include "printf.h"
 #include "sb_fw_update.h"
@@ -608,6 +609,9 @@ void charger_task(void)
 				battery_seems_to_be_dead = 0;
 				prev_ac = curr.ac;
 			}
+#if defined(HAS_TASK_LIGHTBAR) && !defined(HAS_TASK_PDCMD)
+			lightbar_sequence(LIGHTBAR_TAP);
+#endif
 		}
 		charger_get_params(&curr.chg);
 		battery_get_params(&curr.batt);