Bug report

Bug summary
I use matplotlib + PyQt5. The figure is placed inside a QSplitter (a standard Qt widget that consists of several vertical or horizontal parts which can be resized by handles between those parts) . When a part of QSplitter shrinks to a zero size it automatically resizes the widget it contains. Matplotlib raises an error as was mentioned in #16687.

Actual outcome

ValueError: figure size must be positive finite not [17.45  0.  ]

Expected outcome

A zero height figure.

Matplotlib version

• Operating system: Kubuntu 19.10
• Matplotlib version: >=3.2.0 (installed by pip)
• Matplotlib backend: Qt5Agg
• Python version: 3.6.9
• Other libraries: PyQt5