GMap example not showing glyphs

[bryevdv]

With 3.4.0 the scatter markers are not appearing on the gmap example:

https://docs.bokeh.org/en/3.4.0/docs/examples/topics/geo/gmap.html

[bryevdv]

As a (probably) separate aside, GMaps API also warns:

Google Maps JavaScript API has been loaded directly without loading=async. This can result in suboptimal performance. For best-practice loading patterns please see https://goo.gle/js-api-loading

[hakan-77]

@bryevdv I can confirm this is still the case with 3.4.1

[bryevdv]

Triaging for 3.5 but this should ideally be backported to 3.4.x

[mattpap]

This was broken in PR #13554. Projections are applied in secondary glyphs to the original data, leading to invalid coordinates or even NaNs.