add null check for messagesmanager's methods

Change-Id: I257a8c5435db175ef3df5c208d1e447185d3e534
Signed-off-by: Kyeonghun Lee <kh9090.lee@samsung.com>

diff --git a/Tizen.Messaging/Tizen.Messaging.Messages/MessagesManagerImpl.cs b/Tizen.Messaging/Tizen.Messaging.Messages/MessagesManagerImpl.cs
index 63cd9fc..7f8bc21 100755 (executable)
--- a/Tizen.Messaging/Tizen.Messaging.Messages/MessagesManagerImpl.cs
+++ b/Tizen.Messaging/Tizen.Messaging.Messages/MessagesManagerImpl.cs
@@ -103,6 +103,11 @@ namespace Tizen.Messaging.Messages
 
         internal Task<SentResult> SendMessageAsync(Message message, bool saveToSentbox)
         {
+            if (message == null)
+            {
+                MessagesErrorFactory.ThrowMessagesException((int)MessagesError.InvalidParameter);
+            }
+
             var task = new TaskCompletionSource<SentResult>();
 
             _messageSentCallback = (int result, IntPtr data) =>
@@ -127,6 +132,11 @@ namespace Tizen.Messaging.Messages
 
         internal Task<IEnumerable<Message>> SearchMessageAsync(MessagesSearchFilter filter)
         {
+            if (filter == null)
+            {
+                MessagesErrorFactory.ThrowMessagesException((int)MessagesError.InvalidParameter);
+            }
+
             return Task.Run<IEnumerable<Message>>(() =>
             {
                 List<Message> messageList = new List<Message>();