Properly default proxy settings to system settings.
Properly default proxy settings to system settings.

Only apply preference-set values if the values are set in the user preferences or forced by some higher-priority source. This is so we use the system settings as a default instead of stuff defined in recommended policy (which we should just ignore).

BUG=49540
TEST=Configure recommended proxy policy and observe that the system defaults are in effect.

Review URL: http://codereview.chromium.org/4439003

git-svn-id: http://src.chromium.org/svn/trunk/src@65196 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 6b5a14cae7f800c9e90fdba09aafb7ba78115057
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser