This uses a work around AdwBanner not having APIs for setting a
custom child on its internal GtkOverlay child.
It adds a custom widget (CcListRowInfoButton) using the GtkWidget
API and binds the widget visibility to the AdwBanner.visible
property.
This workaround ignores AdwBanner.revealed and relies on its
"visible" property so that we avoid having a "hide" animation when
switching between an app that shows the banner to one that doesn't.
An app page is static populated and the banner is supposed to be
displayed when the page loads and not later.
Fixes#2782
445bc72c7c
