DEPS.xwalk: Re-roll ozone-wayland to 55f39c6.

When we moved to Chromium 35.0.1916.114 (83d22586), we accidentally
reverted ozone-wayland back to f4faec5, thus losing the fix to
XWALK-1673.
Merge pull request #1997 from rakuco/re-roll-oz-wl

DEPS.xwalk: Re-roll ozone-wayland to 55f39c6.
Bump version to 7.35.144.0
[Runtime] WARP security mode should be enabled by default.

According to the W3C widget spec, http://www.w3.org/TR/widgets-access/,
it said: In the default policy, a user agent must deny access to network
resources external to the widget by default, whether this access is
requested through APIs (e.g. XMLHttpRequest) or through
markup (e.g. iframe, script, img). Means if there's no access tag in
config.xml, all external requests should be blocked.

BUG=XWALK-1772