TST: Remove compatibility styling for images that have been updated

If we've updated an image in the past couple commits, then we can remove
the backwards-compatibility styling so that they're generated as
intended.

Author: QuLogic

lib/matplotlib/tests/test_agg_filter.py

@@ -7,9 +7,6 @@
 @image_comparison(baseline_images=['agg_filter_alpha'],
                   extensions=['gif', 'png', 'pdf'])
 def test_agg_filter_alpha():
-    # Remove this line when this test image is regenerated.
-    plt.rcParams['pcolormesh.snap'] = False
-
     ax = plt.axes()
     x, y = np.mgrid[0:7, 0:8]
     data = x**2 - y**2

lib/matplotlib/tests/test_axes.py

@@ -1027,9 +1027,6 @@ def test_hexbin_pickable():
 def test_hexbin_log():
     # Issue #1636 (and also test log scaled colorbar)
 
-    # Remove this line when this test image is regenerated.
-    plt.rcParams['pcolormesh.snap'] = False
-
     np.random.seed(19680801)
     n = 100000
     x = np.random.standard_normal(n)
@@ -1515,9 +1512,6 @@ def test_pcolormesh_log_scale(fig_test, fig_ref):
 
 @image_comparison(['pcolormesh_datetime_axis.png'], style='mpl20')
 def test_pcolormesh_datetime_axis():
-    # Remove this line when this test image is regenerated.
-    plt.rcParams['pcolormesh.snap'] = False
-
     fig = plt.figure()
     fig.subplots_adjust(hspace=0.4, top=0.98, bottom=.15)
     base = datetime.datetime(2013, 1, 1)

lib/matplotlib/tests/test_colors.py

@@ -832,9 +832,6 @@ def _mask_tester(norm_instance, vals):
 
 @image_comparison(['levels_and_colors.png'])
 def test_cmap_and_norm_from_levels_and_colors():
-    # Remove this line when this test image is regenerated.
-    plt.rcParams['pcolormesh.snap'] = False
-
     data = np.linspace(-2, 4, 49).reshape(7, 7)
     levels = [-1, 2, 2.5, 3]
     colors = ['red', 'green', 'blue', 'yellow', 'black']
@@ -852,9 +849,6 @@ def test_cmap_and_norm_from_levels_and_colors():
 @image_comparison(baseline_images=['boundarynorm_and_colorbar'],
                   extensions=['png'], tol=1.0)
 def test_boundarynorm_and_colorbarbase():
-    # Remove this line when this test image is regenerated.
-    plt.rcParams['pcolormesh.snap'] = False
-
     # Make a figure and axes with dimensions as desired.
     fig = plt.figure()
     ax1 = fig.add_axes([0.05, 0.80, 0.9, 0.15])

lib/mpl_toolkits/mplot3d/tests/test_axes3d.py

@@ -654,7 +654,6 @@ def test_surface3d():
 
 @image_comparison(['surface3d_label_offset_tick_position.png'], style='mpl20')
 def test_surface3d_label_offset_tick_position():
-    plt.rcParams['axes3d.automargin'] = True  # Remove when image is regenerated
     ax = plt.figure().add_subplot(projection="3d")
 
     x, y = np.mgrid[0:6 * np.pi:0.25, 0:4 * np.pi:0.25]
@@ -764,7 +763,6 @@ def test_text3d():
 
     ax.text(1, 1, 1, "red", color='red')
     ax.text2D(0.05, 0.95, "2D Text", transform=ax.transAxes)
-    plt.rcParams['axes3d.automargin'] = True  # Remove when image is regenerated
     ax.set_xlim3d(0, 10)
     ax.set_ylim3d(0, 10)
     ax.set_zlim3d(0, 10)
@@ -1243,7 +1241,6 @@ def test_proj_axes_cube():
     for x, y, t in zip(txs, tys, ts):
         ax.text(x, y, t)
 
-    plt.rcParams['axes3d.automargin'] = True  # Remove when image is regenerated
     ax.set_xlim(-0.2, 0.2)
     ax.set_ylim(-0.2, 0.2)
 
@@ -1273,7 +1270,6 @@ def test_proj_axes_cube_ortho():
     for x, y, t in zip(txs, tys, ts):
         ax.text(x, y, t)
 
-    plt.rcParams['axes3d.automargin'] = True  # Remove when image is regenerated
     ax.set_xlim(-200, 200)
     ax.set_ylim(-200, 200)
 
@@ -1735,7 +1731,6 @@ def test_errorbar3d():
 
 @image_comparison(['stem3d.png'], style='mpl20', tol=0.009)
 def test_stem3d():
-    plt.rcParams['axes3d.automargin'] = True  # Remove when image is regenerated
     fig, axs = plt.subplots(2, 3, figsize=(8, 6),
                             constrained_layout=True,
                             subplot_kw={'projection': '3d'})