title: Xamarin Forms - InitializeComponent exception
body: <p>I'm getting an exception on a Xamarin Forms content page with Xaml, on the initializecomponent method.  The exception occurs on the generated xaml.gs page.  I haven't changed any code form a working version.  Maybe something upstream has changed.   The exception message is ""</p>
  
  <p>Value cannot be null.
  Parameter name: binding</p>
  
  <p>stack trace:
    at Xamarin.Forms.BindableObject.SetBinding (Xamarin.Forms.BindableProperty targetProperty, Xamarin.Forms.BindingBase binding, System.Boolean fromStyle) [0x00011] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:293 
    at Xamarin.Forms.BindableObject.SetBinding (Xamarin.Forms.BindableProperty targetProperty, Xamarin.Forms.BindingBase binding) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:117 
    at ....LoginPage.InitializeComponent () [0x00045] in ...\obj\Debug\netstandard2.0\Views\Navigation\Login.xaml.g.cs:34 
    at FieldServices.LoginPage..ctor () [0x0002b] in ..\Views\Navigation\Login.xaml.cs:25 </p>
  
  <p>where occurrs:</p>
  
  <p>[global::System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
          private void InitializeComponent() {
              global::Xamarin.Forms.Xaml.Extensions.LoadFromXaml(this, typeof(LoginPage));
              email = global::Xamarin.Forms.NameScopeExtensions.FindByName(this, "email");
              password = global::Xamarin.Forms.NameScopeExtensions.FindByName(this, "password");
              loginButton = global::Xamarin.Forms.NameScopeExtensions.FindByName(this, "loginButton");
          }</p>