Enable "SafariViewController.hide()" for Chrome Custom Tabs

[avewells]

Implemented fix as discussed in #105. Tested and is working fine in my use-case.

Works with and without <preference name="AndroidLaunchMode" value="singleTask" />. Although without the preference, SafariViewController.hide() causes a new "layer" of the Cordova app to be instantiated. This means that after manually calling SafariViewController.hide() the app's user would lose their place within the app because it's essentially restarting from what I can tell. Because of this, I would recommend that <preference name="AndroidLaunchMode" value="singleTask" /> is added.

Not sure that this would resolve #105, but it does enable SafariViewController.hide() to function on Android as it does iOS.

[kensodemann]

We did some testing on this and noted one minor change that was required to the modified code:

            case "hide": {
                cordova.getActivity().startActivity(new Intent(cordova.getActivity(), cordova.getActivity().getClass()));
                callbackContext.sendPluginResult(new PluginResult(PluginResult.Status.OK, true));
                return true;
            }

Just added the callbackContext.sendPluginResult(new PluginResult(PluginResult.Status.OK, true)); line to inform the webview. Otherwise if your app await's the hide() it will never resolve.

[Azer1652]

@EddyVerbruggen can this be merged?

[msalcala11]

+1 for a merge — just tested this PR, and it works great!