axes.bar supports values given as dict_values yet axes.barh throws an error #14693
Description
Bug report
Bug summary
Calling axes.barh will throw this error if the height of the bars are given as a dictonary values type
TypeError: unsupported operand type(s) for +: 'int' and 'dict_values'
Code for reproduction
import matplotlib.pyplot as plt
data = {'cats': 10, 'dogs': 20}
# Works as expected
fig, ax = plt.subplots(1)
ax.bar(range(len(data)), data.values())
# Doesn't work
fig, ax = plt.subplots(1)
ax.barh(range(len(data)), data.values())
# Works as expected
fig, ax = plt.subplots(1)
ax.barh(range(len(data)), list(data.values()))
plt.show()