Support for Cancelling Drag when Escape key pressed #976
Description
On a normal drag/drop operation pressing Escape ends the drag operation and sets the DropEffect to "none". An event handler has no way of knowing exactly why the drag operation ended, just that there "is nothing to do". With the Rnd component, the DropEffect is presumably always "none" (because it works without a drop target), so there is no way for the component to know whether the drag was cancelled or completed.
There doesn't seem to be a workaround, because calling preventDefault() and stopPropogation() on onDrag event does nothing, and pressing Escape does not interrupt the drag operation.
I have no idea how difficult it would be to address this issue, or whether it's even possible without a hacky solution.
What would really be nice is if Html had a mechanism to indicate the operation was explicitly cancelled.