Fix path computation to also work on Windows
Fix path computation to also work on Windows

BUG=426897
R=kbr@chromium.org
CC=phajdan.jr@chromium.org

Review URL: https://codereview.chromium.org/883013007

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@293980 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build