don't fire click event if default is prevented on mousedown for a drag event

[mollymerp]

fix #6642

in #6218 we stopped checking if the mouse position had changed before firing a click event. the DragPanHandler suppresses its associated click event on mouseup

mapbox-gl-js/src/ui/handler/drag_pan.js

Line 191 in a5a8dfe

DOM.suppressClick();

but if preventDefault() is called on mousedown the click was no longer being suppressed after a drag which caused the change in behavior in #6642

I added a drag simulation that allows you to specify different options for mousedown/mouseup but I'm open to other ideas on how to test this.

Launch Checklist

• briefly describe the changes in this PR
• write tests for all new functionality
• document any changes to public APIs
• manually test the debug page

[jfirebaugh]

I think it's a bit weird to suppress the click based on this particular condition (for instance, why should there be an exception to the suppression if you happen to drag exactly back to the starting position?), but since it was the existing behavior for so long I suppose compatibility does take precedence.

[mollymerp]

yeah I agree its an odd condition to have had in the first place 🤷‍♀️