[NUI] Fix NUI.Components TCT fail (#1541)

diff --git a/src/Tizen.NUI.Components/Utils/StyleManager.cs b/src/Tizen.NUI.Components/Utils/StyleManager.cs
index e057cba..cf562ff 100755 (executable)
--- a/src/Tizen.NUI.Components/Utils/StyleManager.cs
+++ b/src/Tizen.NUI.Components/Utils/StyleManager.cs
@@ -178,7 +178,7 @@ namespace Tizen.NUI.Components
         /// <since_tizen> 8 </since_tizen>
         public void RegisterComponentStyle(string targetTheme, Type component, Type style)
         {
-            if (targetTheme == null)
+            if (targetTheme == null || component == null || style == null)
             {
                 throw new ArgumentException("The argument targetTheme must be specified");
             }