…12136)This combines `get_normals` and `_generate_normals`, and eliminates all other calls to np.cross.`get_normals` and `_generate_normals` were profiled, and it was found that vectorizing `np.cross`  like in `get_normals` was faster:```pythonimport numpy as npdef get_normals(polygons):    v1 = np.empty((len(polygons), 3))    v2 = np.empty((len(polygons), 3))    for poly_i, ps in enumerate(polygons):        # pick three points around the polygon at which to find the        # normal doesn't vectorize because polygons is jagged        i1, i2, i3 = 0, len(ps)//3, 2*len(ps)//3        v1[poly_i, :] = ps[i1, :] - ps[i2, :]        v2[poly_i, :] = ps[i2, :] - ps[i3, :]    return np.cross(v1, v2)def _generate_normals(self, polygons):    normals = []    for verts in polygons:        v1 = np.array(verts[0]) - np.array(verts[1])        v2 = np.array(verts[2]) - np.array(verts[0])        normals.append(np.cross(v1, v2))    return np.array(normals)polygons = [    np.random.rand(np.random.randint(10, 1000), 3)    for i in range(100)]%timeit _generate_normals(polygons)# 3.14 ms ± 255 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)%timeit get_normals(polygons)# 452 µs ± 4.33 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)```

* upstream/master: (1723 commits)  Correctly get weight & style hints from certain newer Microsoft fonts (matplotlib#12945)  Remove some checks for Py<3.6 in the test suite. (matplotlib#12974)  Fail-fast when trying to run tests with too-old pytest.  Include scatter plots in Qt figure options editor. (matplotlib#12779)  ENH: replace deprecated numpy header  Minor simplifications.  tickminorvisible-fix (matplotlib#12938)  Remove animated=True from animation docs  Update the documentation of Cursor  Misc. cleanups.  Add test for 3d conversion of empty PolyCollection  Support ~ as nonbreaking space in mathtext.  Deprecate public use of Formatter.pprint_val.  MAINT: Unify calculation of normal vectors from polygons (matplotlib#12136)  Fix the title of testing_api  More table documentation  Simplify bachelors degree example using new features.  Avoid pyplot in showcase examples.  Simplify argument checking in Table.__getitem__. (matplotlib#12932)  Minor updates following bump to Py3.6+.  ...# Conflicts:#lib/matplotlib/widgets.py