keyframe curves go through the roof
@jeff
Submitted by Jeff F.T. Assigned to Jeff F.T. @jeff
Description
If you put a curve at 100% or 0%, it's flush with the clip border and half hidden and harder to manipulate.
We need to subtract the 2*stroke_width from the height of the clip.
Imported from https://bugzilla.gnome.org/show_bug.cgi?id=589689