Calibrate the coordinates based on frame position.
Calibrate the coordinates based on frame position.

Since the toolbar lives outside the canvas frame, the event's generated on it
have clientX and clientY relative to the page. This makes sure we consider
frame offset from the page.

Fixes #2207,#2372

artf/grapesjs,artf/grapesjs,QuorumDMS/grapesjs,artf/grapesjs,QuorumDMS/grapesjs