Bad xlim/ylim when using shared axes subplots and an empty subplot

[ChrisBeaumont]

The following code

fig, axes = plt.subplots(nrows=1, ncols=2, sharex=True, sharey=True)
axes[0].plot([1,2,3])
print axes[0].get_xlim(), axes[0].get_ylim()
plt.show()

outputs

(-0.059999999999999998, 0.059999999999999998) (-0.059999999999999998, 0.059999999999999998)

The axis limits are only updated to sane values once the second axes is populated with something.

If a subplot with shared axes is empty, I expect the view limits to be set according to the non-empty plots

[dmcdougall]

Resolved in #2357.