Upstream cpplint.py r79 ("Convert windows path seperators to unix like while doing IncludeWhatYouUse.")

Review URL: http://codereview.chromium.org/9159036

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@119713 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/cpplint.py b/cpplint.py
index c985c5d..9c7b8b4 100755
--- a/cpplint.py
+++ b/cpplint.py
@@ -3054,7 +3054,7 @@
   header_found = False
 
   # Use the absolute path so that matching works properly.
-  abs_filename = os.path.abspath(filename)
+  abs_filename = FileInfo(filename).FullName()
 
   # For Emacs's flymake.
   # If cpplint is invoked from Emacs's flymake, a temporary file is generated