Remove xdisplaycheck from the tree

R=dpranke@chromium.org,ben@chromium.org
BUG=670470

Review-Url: https://codereview.chromium.org/2530463002
Cr-Original-Commit-Position: refs/heads/master@{#436624}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: cca74e347e8b31645821402157065c7240d79f3f