Set the default shutdown timeout to 5s.

When shutting down, allow services to exit cleanly by sending them a
SIGTERM signal and waiting 5 seconds before rebooting.

Bug: 26216447
Test: manual: `power_example --action=shut_down`. All services exit
cleanly then the system reboots.

Change-Id: I4c1c0e42ce9d0ca86381c790f2d28d22f2bb06e9
diff --git a/brillo_base.mk b/brillo_base.mk
index 5a28fdf..94d21ab 100644
--- a/brillo_base.mk
+++ b/brillo_base.mk
@@ -328,7 +328,8 @@
 # On Android this is defined in embedded.mk, see
 # https://android-review.googlesource.com/#/c/106470.
 PRODUCT_DEFAULT_PROPERTY_OVERRIDES += \
-    debug.atrace.tags.enableflags=0
+    debug.atrace.tags.enableflags=0 \
+    ro.build.shutdown_timeout=5 \
 
 # Define a make variable that identifies Brillo targets.
 BRILLO := 1