title: Axes.invert_axis() does not work with sharey=True for matplotlib subplots
body: <p>I am trying to make 4 subplots (2x2) with an inverted y axis while also sharing the y axis between subplots. Here is what I get:</p>
  
  <pre><code>import matplotlib.pyplot as plt
  import numpy as np
  
  fig,AX = plt.subplots(2, 2, sharex=True, sharey=True)
  
  for ax in AX.flatten():
      ax.invert_yaxis()
      ax.plot(range(10), np.random.random(10))
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/QEsM2.png" alt="enter image description here"></p>
  
  <p>It appears that <code>ax.invert_axis()</code> is being ignored when <code>sharey=True</code>. If I set <code>sharey=False</code> I get an inverted y axis in all subplots but obviously the y axis is no longer shared among subplots. Am I doing something wrong here, is this a bug, or does it not make sense to do something like this?</p>