Bug report

I've started trying to get Cartopy working with the latest Matplotlib releases. Currently a lot of things fail, but there are some new things in 3.2.0rc1 that we may want to fix before releasing. Unfortunately, all those existing failures make it difficult to determine what's new, but I believe the following are introduced by 3.2.0rc1.

Code for reproduction

$ conda create -p /tmp/cpmpl matplotlib-base cartopy filelock
$ conda activate /tmp/cpmpl
$ pip install matplotlib==3.2.0rc1
$ pytest --pyargs cartopy -k 'test_limits_contour or test_contour_plot_bounds or test_global_contourf_wrap_no_transform or test_pcolormesh_goode_wrap or test_pcolormesh_mercator_wrap'

Actual outcome
For test_limits_contour:

E AssertionError: 
E Arrays are not almost equal to 6 decimals
E 
E x and y +inf location mismatch:
E x: array([[ inf, inf],
E [-inf, -inf]])
E y: array([[ 70., -45.],
E [170., 45.]])

For test_contour_plot_bounds:

E AssertionError: 
E Arrays are not almost equal to 6 decimals
E 
E Mismatch: 100%
E Max absolute difference: 3230840.45
E Max relative difference: 0.99999998
E x: array([-0.05, 0.05, -0.05, 0.05])
E y: array([-2763217. , 2681906. , -263790.62, 3230840.5 ])

For test_global_contourf_wrap_no_transform:
The test image is cropped into a very small area.

For test_pcolormesh_goode_wrap, and test_pcolormesh_mercator_wrap:
The left edge of the image is visibly cropped.

Expected outcome

Tests pass.

Matplotlib version

• Operating system: Fedora 30
• Matplotlib version: 3.2.0rc1
• Matplotlib backend (print(matplotlib.get_backend())): Agg
• Python version: 3.7
• Other libraries: Cartopy 0.17.0