LoginAsync treats cancel the same as error

[ghost]

When calling FacebookSessionClient.LoginAsync, there is no difference in the handling between when an error occurs (WebAuthenticationStatus.ErrorHttp) or when a user cancels the operation (WebAuthenticationStatus.UserCancel). Both result in a plain InvalidOperationException being thrown.

In practice, one might want to distinguish between the two. I want to do something different to my users when they press the back button as when, for example, the device has no internet connection. As it stands, there is no way to make this distinction.

[f2bo]

+1

Returning more specific exceptions, or at least different error messages would be better.
@ntotten: we need this for the controls.

[ghost]

Turns out this is a duplicate of issue #17.

[sanjeevdwivedi]

duplicate. Closing. See #17