Fix axes_position test to use text encoding.
Fix axes_position test to use text encoding.

rmgorman/google-chartwrapper,appknox/google-chartwrapper,Bulletninja/google-chartwrapper,google-code-export/google-chartwrapper,Bulletninja/google-chartwrapper,appknox/google-chartwrapper,appknox/google-chartwrapper,rmgorman/google-chartwrapper,google-code-export/google-chartwrapper,simplyvikram/google-chartwrapper,simplyvikram/google-chartwrapper