CB-7674 move preference activation back into onCreate()

The preference creation actually needs to be before
super.onCreate(savedInstance) in order to avoid the exception
"requestFeature() must be called before adding content". Also ran into an
issue in the native tests "Whitelist" and "User WebView/Client/Chrome" where
it would throw an exception that the CordovaWebView appView already had
a parent and needed to be removed from that parent before the invocation
to root.addView(appView). So I conditionally remove the wrong parent.
Also made a change to the native tests so the menus test would work.
I also put super.init() back into the template, though invoking it is optional
as loadUrl will call it automatically if needed.