[Timer applet] Fix double speed countdown & commands run multiple times
Both the compact and the fullpresentation variants of the applet had
an instance of a timer, and both were connected to the central "running"
flag. So if both variants had been created, there were 2 timers triggering
the decreasing of the seconds, and also firing off the command once done.
Moving the countdown timer (and at the same time also a timer for
delayed saving of the state, which had the same issue) to the central root
item fixes this.
Applet still works as before on panel and background pane, now does proper
countdown in both cases.
Reviewers: Plasma, davidedmundson
Reviewed By: Plasma, davidedmundson
Subscribers: davidedmundson, plasma-devel
Differential Revision: https://phabricator.kde.org/D13065