Some of the calls to *::FromUnknownPoint in AsyncPanZoomController.cpp were inserted early in the conversion process when converting from things that were gfx::Point. Now that those things have been converted over, we should be able to remove the FromUnknownPoint calls. For example, at  the TapGestureInput::mPoint has been converted, so the FromUnknownPoint there can be removed.
Created attachment 773451 [details] [diff] [review]
Note: I didn't find any uses of FromUnknownRect that fit the bill. I also checked FromUnknownSize, and ToUnknown*, and again there was nothing.
Try results: https://tbpl.mozilla.org/?tree=Try&rev=5769c58c1064