remoting/host: Fix the cros chrome-sdk build.

Remove x_server_clipobard_unittest.cc from any build that does not
use_x11.

R=yuweih@chromium.org

Bug: 867013
Test: none
Change-Id: I015bbedd34b2f1cd1d65f54f3cb6dc4d3ad76d4e
Reviewed-on: https://chromium-review.googlesource.com/1150631
Reviewed-by: Yuwei Huang <yuweih@chromium.org>
Commit-Queue: James Hawkins <jhawkins@chromium.org>
Cr-Commit-Position: refs/heads/master@{#578052}
1 file changed