All events in month-popover displays hour-label indicating their start time,
but all-day events should not display their start time.
This is caused by gtk_widget_show_all recursively setting the events list-box
and all its childrens visible.
We replace gtk_widget_show_all with gtk_widget_show to show the events list-box
and its childrens.
https://gitlab.gnome.org/GNOME/gnome-calendar/issues/250
On HiDPI displays, the color boxes of timed events
appear distorted and not squared.
Fix that by setting a fixed size, and changing the
box alignment to always shrink to a squared state.
The current GcalEventWidget implementation is a direct
GtkWidget subclass, which means we have to take care of
all the implementation details such as raising GdkWindows
and managing the drawing all by ourselves.
The event widget, however, can be easily described through
a GtkBuilder file. This would simplify the implementation
and makes us maintain less code.
Fix that by making GcalEventWidget a GtkBin subclass.
Abdullahi Usman