Adding logic to detect and log invalid RDP settings
Adding logic to detect and log invalid RDP settings

This change adds code that checks the values of a set of registry keys which
have specific required values, otherwise we know we cannot establish an RDP
session.  The code will log an error if the incorrect value is found and will
prevent the RDP session from being created.  If for some reason we fail to read
the registry key, a warning will be logged but we won't prevent the attempt to
create an RDP session.

BUG=506555

Review-Url: https://codereview.chromium.org/1944513002
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#391338}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk