smartlist: fix crash when we delete a contact

When we delete a system contact by clicking on the photo in the
smartlist and then we restart the application, the smartlist does not
loaded because the contact is null.

Checks are added to fixes this problem.

Change-Id: Iff0ffbb6c6ef99e6051e14f288bc1bb709a2f1d5
Reviewed-by: Hadrien De Sousa <hadrien.desousa@savoirfairelinux.com>

ring-android/app/src/main/java/cx/ring/services/ContactServiceImpl.java

@@ -219,7 +219,10 @@ public class ContactServiceImpl extends ContactService {
                 contentUri = ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI, id);
             }
 
-            Cursor result = contentResolver.query(contentUri, CONTACT_PROJECTION, null, null, null);
+            Cursor result = null;
+            if (contentUri != null) {
+                result = contentResolver.query(contentUri, CONTACT_PROJECTION, null, null, null);
+            }
 
             if (result == null) {
                 return null;

ring-android/libringclient/src/main/java/cx/ring/services/ContactService.java

@@ -247,7 +247,9 @@ public abstract class ContactService extends Observable {
         if (contact == null && (settings.isAllowSystemContacts() && mDeviceRuntimeService.hasContactPermission())) {
             Log.w(TAG, "getContactById : cache miss for " + id);
             contact = findContactByIdFromSystem(id, key);
-            mContactList.put(id, contact);
+            if (contact != null) {
+                mContactList.put(id, contact);
+            }
         }
         return contact;
     }