Fix simply window stack to use NONE
Fix simply window stack to use NONE

Some compilers warn on unused values by default. Use NONE instead of NULL for
empty statements.

daduke/LMSController,bkbilly/Tvheadend-EPG,fletchto99/pebblejs,pebble/pebblejs,carlo-colombo/dublin-bus-pebble,pebble/pebblejs,fletchto99/pebblejs,jiangege/pebblejs-project,jsfi/pebblejs,jsfi/pebblejs,bkbilly/Tvheadend-EPG,bkbilly/Tvheadend-EPG,carlo-colombo/dublin-bus-pebble,sunshineyyy/CatchOneBus,pebble/pebblejs,carlo-colombo/dublin-bus-pebble,sunshineyyy/CatchOneBus,jiangege/pebblejs-project,daduke/LMSController,jiangege/pebblejs-project,fletchto99/pebblejs,pebble/pebblejs,fletchto99/pebblejs,youtux/PebbleShows,pebble/pebblejs,jiangege/pebblejs-project,bkbilly/Tvheadend-EPG,sunshineyyy/CatchOneBus,sunshineyyy/CatchOneBus,daduke/LMSController,daduke/LMSController,sunshineyyy/CatchOneBus,carlo-colombo/dublin-bus-pebble,youtux/PebbleShows,jiangege/pebblejs-project,bkbilly/Tvheadend-EPG,fletchto99/pebblejs,youtux/PebbleShows,jsfi/pebblejs,daduke/LMSController,carlo-colombo/dublin-bus-pebble,jsfi/pebblejs,youtux/PebbleShows,jsfi/pebblejs