[PATCH] [GraphWriter] Attempt to open .dot files with xdg-open/open first

[Matthias Braun]

I have it set to /Applications/GraphViz.app (from a macos "development snapshot" from graphviz.org http://graphviz.org/ download area). The generated .ps files tended to look very strange for me (lots of whitespace so I had to zoom in before I could really see the graph).


REPOSITORY
  rL LLVM

http://reviews.llvm.org/D6534

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/