Only display error adorner after user interaction.

Fixes #307.

Author: grokys

src/GitHub.UI.Reactive/Controls/Validation/ValidationMessage.cs

@@ -17,6 +17,7 @@ namespace GitHub.UI
     public class ValidationMessage : UserControl
     {
         const double defaultTextChangeThrottle = 0.2;
+        bool userHasInteracted;
 
         public ValidationMessage()
         {
@@ -33,7 +34,7 @@ public ValidationMessage()
                 .Do(CreateBinding)
                 .Select(control =>
                     Observable.Merge(
-                        this.WhenAnyValue(x => x.ShowError),
+                        this.WhenAnyValue(x => x.ShowError).Where(x => userHasInteracted),
                         control.Events().TextChanged
                             .Throttle(TimeSpan.FromSeconds(ShowError ? defaultTextChangeThrottle : TextChangeThrottle),
                             RxApp.MainThreadScheduler)
@@ -121,6 +122,7 @@ public string ErrorAdornerTemplate
         void ShowValidateError(bool showError)
         {
             IsShowingMessage = showError;
+            userHasInteracted = true;
 
             if (ValidatesControl == null || !IsAdornerEnabled()) return;