As stated in the PDF specification ISO 32000-1, table in Annex D.2 Latin Character Set and Encodings page 653 to 656 (available here: http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/PDF32000_2008.pdf):
"The SPACE character shall also be encoded as 312 in MacRomanEncoding and as 240 in WinAnsiEncoding. This duplicate code shall signify a nonbreaking space; it shall be typographically the same as (U+003A) SPACE."
The duplicate key was missing, therefore PDFMiner was returning the string "(cid:160)".
This fix adds the duplicate key in latin_enc.py
glyphlist.py does not need to be modified as it already contains a key for non breaking space https://github.com/lucanaso/pdfminer/blob/master/pdfminer/glyphlist.py#L2755.