Review Mozilla 1680669 and 1833963: Ship fractional coordinates of Pointer Events

Bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1680669 and https://bugzilla.mozilla.org/show_bug.cgi?id=1833963

Now supports non-integer values for MouseEvent.clientX etc. Should make things better for zoomed content. But also a potential fingerprint measure.

Upstream has a preference dom.event.pointer.fractional_coordinates.enabled to switch this off. Not sure how long this will stay in place or be supported.

Edited Apr 02, 2025 by henry

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