GitLab

Removed ONC proxy policy applied check when the default network is
changed.

If proxy settings are bundled to the specific network and another
network is connected on startup, these settings are not
transferred to ARC on startup and should be transferred only when the network
becomes a default netowork.

BUG=657361
TEST=browsertest

Review-Url: https://codereview.chromium.org/2436753002
Cr-Commit-Position: refs/heads/master@{#427058}