Enabling uninitialized trigger also sets score to 0

The bug

When you enable a trigger scoreboard objective for a player who has no score for it yet, the value is initialized to 0. This can cause problems if you use 0 as a value for an action.

The use for it might be to tell that a trigger objective was enabled, but in this case any scoreboard command changing the value before the test happens negates this use.

How to reproduce

1. /scoreboard objectives add triggerObjective trigger
2. /scoreboard players list @p
   → triggerObjective is not shown
3. /scoreboard players enable @p triggerObjective
4. /scoreboard players list @p
   → triggerObjective is shown with a value of 0

Additional comment