ninja: Revert accidental windows changes in r1871.
ninja: Revert accidental windows changes in r1871.

TBR=scottmg@chromium.org

Review URL: https://codereview.chromium.org/198283004

git-svn-id: e7e1075985beda50ea81ac4472467b4f6e91fc78@1872 78cadc50-ecff-11dd-a971-7dbc132099af

pyokagan/gyp,pyokagan/gyp,svn2github/gyp,pyokagan/gyp,svn2github/gyp,svn2github/gyp,svn2github/kgyp,svn2github/kgyp,luvit/gyp,svn2github/gyp,pyokagan/gyp,svn2github/kgyp,luvit/gyp,luvit/gyp,svn2github/kgyp,pyokagan/gyp,svn2github/gyp,luvit/gyp,svn2github/kgyp