Consider removing pointermove (and interactionType and pointerIsDragSet)

[mmocny]

...as used by the steps of computing interactionID

As far as I can tell, this is computed but isn't actually exposed at all. It seems not used in computing any other values.

In addition, in Chromium we found that the approach specified can be misleading. For example, there is a certain movement threshold distance before a pointer interaction actually becomes a "drag" and not a "tap". The mere dispatch of a move event is not enough signal to make this distinction. Rather than making this more complicated to account for this, it seems best to just remove this distinction.

(There is is also generally a thin line sometimes between what a user considers a tap or drag, better to just not try to label)