Unable to render spans less than 1ms

[bg451]

If a span takes microseconds instead of milliseconds to complete, the UI is simply unable to render them and the profile view shows all values as 0.

[alanjds]

This line caps to ms before sending the trace to the front (kudos @LuizArmesto for figuring it out).

Maybe someone that knows how to deal with vsfgen generation stuff can handle from now. I gave up on vsfgen for today.