Tooltips in GtkOverlay are mixed up
Submitted by Timm Bäder
Created attachment 277320 Testcase to reproduce the problem
If the overlay child in a GtkOverlay has a tooltip_text set, it's never shown. If the GtkOverlay's normal child has no tooltip_text set, no tooltip is shown at all. If the GtkOverlay's normal child has a tooltip_text set, that one is shown instead.
Reproducible with both 3.12.2 and current master.
(Side note: I've coincidentally noticed that if the overlay child is moved under the cursor -- in this case by an animated scrolling movement -- the tooltip of the overlay child does get shown. I don't know if this is related but it might be good to know)
Attachment 277320, "Testcase to reproduce the problem":