examples/canvas: Resize the canvas on allocation changes
examples/canvas: Resize the canvas on allocation changes

This should show how to make a Canvas resize whenever the actor that
uses it as content changes size. For good measure, it also shows how to
coalesce multiple allocations into one Canvas resize through a timeout
source.

GNOME/clutter,djdeath/clutter,Distrotech/clutter,kerrickstaley/clutter-vala,djdeath/clutter-android,ebassi/clutter,GNOME/clutter,djdeath/clutter-android,jigpu/clutter,djdeath/clutter-android,Distrotech/clutter,djdeath/clutter,jigpu/clutter,heysion/clutter-clone,heysion/clutter-clone,jigpu/clutter,jigpu/clutter,GNOME/clutter,jigpu/clutter,Distrotech/clutter,djdeath/clutter,collects/clutter,Distrotech/clutter,GNOME/clutter,kerrickstaley/clutter-vala,kerrickstaley/clutter-vala,djdeath/clutter,collects/clutter,heysion/clutter-clone,kerrickstaley/clutter-vala,ebassi/clutter,heysion/clutter-clone,djdeath/clutter-android,ebassi/clutter,collects/clutter,collects/clutter,jigpu/clutter,Distrotech/clutter,collects/clutter,GNOME/clutter,Distrotech/clutter,djdeath/clutter,ebassi/clutter,ebassi/clutter,heysion/clutter-clone,djdeath/clutter,djdeath/clutter-android