Resolving warnings in Win32 console at shutdown

[callum]

Windows CEF 2454, 32bit

I see this message in the console at shut down for a Release configuration:
"[0730/183955:WARNING:pref_notifier_impl.cc(27)] pref observer found at shutdown proxy"

and in a Debug configuration:
[1001/112425:WARNING:content_browser_client.cc(547)] No browser info matching frame process id 3 and routing id 1

What step(s) have I missed in the shutdown code?