system_api: remove never-used property name

Remove the never-used kPrependDNSServersProperty value from shill's
Manager's exported interface.

BUG=none
TEST=emerge-amd64-generic system_api

Change-Id: I2ba2a0037cde5fd16c3382b78478feb382b5cd78
Reviewed-on: https://chromium-review.googlesource.com/251481
Commit-Queue: Garret Kelly <gdk@chromium.org>
Trybot-Ready: Garret Kelly <gdk@chromium.org>
Tested-by: Garret Kelly <gdk@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
1 file changed
tree: 03c6f9e79a736177cc1fe8a30038135e9fed9346
  1. constants/
  2. dbus/
  3. switches/
  4. OWNERS
  5. README
  6. system_api.gyp
  7. system_api.pc