Should eraser clear the timer?

[KatieWoe]

Test device
ChromeBook
Operating System
ChromeOS
Browser
Chrome
Problem description
For phetsims/qa#1068
When you press the eraser button the timer does not reset, even though the projectile it measured is gone. This may need a second look.

[matthew-blackman]

Reviewed this with @samreid and all looks good. Labeling ready to cherry-pick.

[matthew-blackman]

Please close after verifying.

[KatieWoe]

Seems fixed. I did notice that this may be complicated by switching fields. As it is, the timer is not affected by switching fields, so if you start it and switch fields, it is still active, and if you erase the new field the time is reset, even thought the ball it was originally measuring still exists in the first field. At this point this is so minor and I'm not sure another behavior would actually be preferable. But I wanted to check before closing.

[Nancy-Salpepi]

I noticed the same behavior @KatieWoe reported in #297 (comment) while I was testing over the weekend.

[matthew-blackman]

Great find @KatieWoe and @Nancy-Salpepi! Continuing over in #320. Can this issue be closed?

[KatieWoe]

Sure!