Test faliures after merging the decxx branch (#3646)

[jenshnielsen]

After merging #3646 I see a bunch of failures like this one with python 3.4.1:

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ERROR: matplotlib.tests.test_artist.test_cull_markers
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Traceback (most recent call last):
  File "/usr/local/lib/python3.4/site-packages/nose/case.py", line 198, in runTest
    self.test(*self.arg)
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/testing/decorators.py", line 110, in wrapped_function
    func(*args, **kwargs)
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/tests/test_artist.py", line 139, in test_cull_markers
    fig.savefig(pdf, format="pdf")
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/figure.py", line 1470, in savefig
    self.canvas.print_figure(*args, **kwargs)
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/backend_bases.py", line 2194, in print_figure
    **kwargs)
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/backends/backend_pdf.py", line 2474, in print_pdf
    file.close()
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/backends/backend_pdf.py", line 525, in close
    self.writeFonts()
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/backends/backend_pdf.py", line 628, in writeFonts
    fonts[Fx] = self.embedTTF(realpath, chars[1])
  File "/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib-1.5.x-py3.4-macosx-10.10-x86_64.egg/matplotlib/backends/backend_pdf.py", line 1056, in embedTTF
    pclt = font.get_sfnt_table('pclt') or {'capHeight': 0, 'xHeight': 0}
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte

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I.e. a large number of pdf tests using fonts fails. Not sure why travis doesn't hit this.

This is on OSX 10.10 with python installed from homebrew. The tests passes with Python 2.7

I did not test with python 3 before the merge.

[mdboom]

It probably occurs with a specific font on your system. Travis has very few fonts installed.

It would be helpful to know what this font is -- print out "font.fname" on the line above.