markeredgecolor none visibility bug in 1.5.x (re-opening #598)

[azjps]

Plotting with markeredgecolor="none" causes markers to not display (probably fully transparent) in current master 1.5.x. It might be related to this pull request. The plot in Out[3] below does not show anything. In matplotlib 1.4 it displays markers as expected.

~/matplotlib (master)$ ipython
Python 2.7.6 (default, Aug 25 2014, 18:32:19) 
Type "copyright", "credits" or "license" for more information.

IPython 2.2.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

In [1]: %matplotlib
Using matplotlib backend: TkAgg

In [2]: import matplotlib; import matplotlib.pyplot as plt; import numpy as np

In [3]: plt.plot(np.arange(3), 'ro', mec='none')
Out[3]: [<matplotlib.lines.Line2D at 0x4171610>] 

In [4]: matplotlib
Out[4]: <module 'matplotlib' from '/apps/stonefs1/azhu/venv/el5-stonelib/lib/python2.7/site-packages/matplotlib-1.5.x-py2.7-linux-x86_64.egg/matplotlib/__init__.pyc'>

In [5]: matplotlib.__version__
Out[5]: '1.5.x'

[tacaswell]

cc @mdboom I assume this is more fall out from the cxx refactoring

[mdboom]

I think this is a dupe of #3687, which is actually not related to the cxx refactoring, but is caused by #3514. Which actually suggests that #3687 should be backported to v1.4.x.

[tacaswell]

This is a duplicate of #3687 which has been merged. If this is not fixed, please ping to have re-opened.