Fixes from Spaceship

CHANGELOG.md

 
 ## 2019.3.7
 
-#### Added
-
-* Fixed Take Screenshot Action : bad filename + tooltips
+* Fixed Take Screenshot Action : Bad Filename + Added Tooltips
+* Fixed property name in NonNullCheck property drawer
+* Fixed Potential null in Discover Window
 
 ## 2019.3.6
 

Editor/Discover/DiscoverWindow.cs

             EditorSceneManager.sceneOpened -= UpdateDiscoverObjectsOnLoad;
             EditorSceneSetup.onSetupLoaded -= UpdateDiscoverObjectsOnLoadSetup;
 
-            if (s_Windows.Contains(this))
+            if (s_Windows != null && s_Windows.Contains(this))
                 s_Windows.Remove(this);
         }
 

Editor/PropertyDrawers/NonNullCheckPropertyDrawer.cs

                 bool valid = property.objectReferenceValue != null;
                 var color = GUI.backgroundColor;
                 GUI.backgroundColor = valid ? color : Color.red; 
-                EditorGUI.ObjectField(position, property, new GUIContent(ObjectNames.NicifyVariableName(property.name)));
+                EditorGUI.ObjectField(position, property);
                 GUI.backgroundColor = color;
             }
             else