fix editable bug

Runtime/rendering/editable.cs

                 else if (!this._selection.isCollapsed && this._selectionColor != null) {
                     showSelection = true;
                 }
+                this._updateSelectionExtentsVisibility(effectiveOffset);
             }
 
             if (showSelection) {

Runtime/widgets/text_selection.cs

 using Unity.UIWidgets.scheduler;
 using Unity.UIWidgets.service;
 using Unity.UIWidgets.ui;
+using Rect = Unity.UIWidgets.ui.Rect;
 
 namespace Unity.UIWidgets.widgets {
     static class TextSelectionUtils {
                             offset: value.selection.start + data.text.Length
                         )
                     );
+                    
+                    selectionDelegate.bringIntoView(selectionDelegate.textEditingValue.selection.extendPos);
+                    selectionDelegate.hideToolbar();
-
-                selectionDelegate.bringIntoView(selectionDelegate.textEditingValue.selection.extendPos);
-                selectionDelegate.hideToolbar();
             });
         }