Intent to unship: `PointerEvent.getCoalescedEvents()` in insecure context

[Masayuki Nakano]

Summary: `PointerEvent.getCoalescedEvents()` is defined as an API only in secure context. However, we exposed this API to insecure context too and we stop doing this incorrect behavior.

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1986831

Platform coverage: All platforms.

Preference: dom.w3c_pointer_events.getcoalescedevents_only_in_securecontext

DevTools bug: N/A

Other browsers: The other browsers do not expose this API in both stable and experimental builds.

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Masayuki Nakano <masa...@d-toybox.com>
Working on DOM, Events, editor and IME handling for Gecko