Update raw_editor.dart

lib/src/widgets/raw_editor.dart

@@ -722,6 +722,7 @@ class RawEditorState extends EditorState
   }
 
 KeyEventResult _handleSpaceKey(RawKeyEvent event) {
+    try {
       final child =
           controller.document.queryChild(controller.selection.baseOffset);
       if (child.node == null) {
@@ -733,6 +734,10 @@ class RawEditorState extends EditorState
         return KeyEventResult.ignored;
       }
 
+      if (line.first == null) {
+        return KeyEventResult.ignored;
+      }
+
       final text = castOrNull<leaf.Text>(line.first);
       if (text == null) {
         return KeyEventResult.ignored;
@@ -748,8 +753,11 @@ class RawEditorState extends EditorState
       } else {
         return KeyEventResult.ignored;
       }
+    } catch (e) {
+      print("Caught exception: $e");
+    }
 
-    return KeyEventResult.handled;
+    return KeyEventResult.ignored;
   }
 
   KeyEventResult _handleTabKey(RawKeyEvent event) {