Backport PR #42803: COMPAT: MPL 3.4.0 (#42807)

Co-authored-by: Thomas Li <[email protected]>

Author: meeseeksmachine

pandas/plotting/_matplotlib/tools.py

@@ -414,8 +414,12 @@ def handle_shared_axes(
             except IndexError:
                 # if gridspec is used, ax.rowNum and ax.colNum may different
                 # from layout shape. in this case, use last_row logic
+                if compat.mpl_ge_3_4_0():
+                    is_last_row = lambda x: x.get_subplotspec().is_last_row()
+                else:
+                    is_last_row = lambda x: x.is_last_row()
                 for ax in axarr:
-                    if ax.is_last_row():
+                    if is_last_row(ax):
                         continue
                     if sharex or _has_externally_shared_axis(ax, "x"):
                         _remove_labels_from_axis(ax.xaxis)