Bug report

Bug summary

Titles cannot be padded to negative numbers anymore.
Only if no xticklabels are on the axes, it still works as expected.

This broke in #13741 (sorry for approving that one)

Code for reproduction

import matplotlib.pyplot as plt

fig, (ax1, ax2) = plt.subplots(ncols=2)
for ax in (ax1, ax2):
    ax.set_title(f"Title 1", pad=-20)

ax1.tick_params(labelbottom=False)

plt.show()

Actual outcome

Expected outcome

Matplotlib version

• Operating system:
• Matplotlib version: 3.1
• Matplotlib backend (print(matplotlib.get_backend())):
• Python version:
• Jupyter version (if applicable):
• Other libraries: