[Preference] add exception when set value is null

Change-Id: I14bf13873d2f8070eef1f05babdd317a53fafe55
Signed-off-by: SukHyung, Kang <shine.kang@samsung.com>

diff --git a/src/Tizen.Applications.Preference/Tizen.Applications/Preference.cs b/src/Tizen.Applications.Preference/Tizen.Applications/Preference.cs
index 42311fc..84000c7 100755 (executable)
--- a/src/Tizen.Applications.Preference/Tizen.Applications/Preference.cs
+++ b/src/Tizen.Applications.Preference/Tizen.Applications/Preference.cs
@@ -215,6 +215,11 @@ namespace Tizen.Applications
                     throw PreferenceErrorFactory.GetException(ret);
                 }
             }
+            else
+            {
+                Log.Error(LogTag, "Failed to Set");
+                throw new ArgumentException("Invalid parameter");
+            }
         }
 
         /// <summary>