Disable GN call, it breaks the win perf builder.

BUG=326146
TBR=brettw@chromium.org

Review URL: https://codereview.chromium.org/104043003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238982 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 238982