Update DEPS.xwalk to include new patch in Chromium

https://github.com/crosswalk-project/crosswalk/pull/1539
This PR depends on the patch in Chromium, with PR
https://github.com/crosswalk-project/chromium-crosswalk/pull/115

BUG=https://crosswalk-project.org/jira/browse/XWALK-880