Importing the Salesforce Summer 17 (v40.0) Tooling and Metadata APIs to .NET

The Salesforce Summer '17 release includes the return of an old friend in both the Tooling and Metadata APIs. After refreshing to the latest WSDLs and making sure the project builds it starts producing errors like the following with calling the API:

error CS0029: Cannot implicitly convert type 'XYZ.SalesforceConnector.SalesforceTooling.NavigationMenuItem' to 'XYZ.SalesforceConnector.SalesforceTooling.NavigationMenuItem[]'

I say it's an old friend, because I've seen this before with the Partner API when it transitioned to Winter '15 (v32.0) for the QuickActionLayoutItem. It's also cropped up with Winter '13 (v29.0). Thankfully the same fix that was applied in those cases will also work here.

The problem is the navigationLinkSet property that gets generated with a multidimensional array return type. The type for the corresponding XmlArrayItemAttribute is incorrect.

Before Fix

/// 
[System.Xml.Serialization.XmlArrayItemAttribute("navigationMenuItem", typeof(NavigationMenuItem), IsNullable=false)]
public NavigationMenuItem[][] navigationLinkSet {
    get {
        return this.navigationLinkSetField;
    }
    set {
        this.navigationLinkSetField = value;
    }
}

After Fix

/// 
[System.Xml.Serialization.XmlArrayItemAttribute("navigationMenuItem", typeof(NavigationMenuItem[]), IsNullable=false)]
public NavigationMenuItem[][] navigationLinkSet {
    get {
        return this.navigationLinkSetField;
    }
    set {
        this.navigationLinkSetField = value;
    }
}

The same fix needs to be applied to both the Tooling API and the Metadata API.