Description

Before this PR, if you set a TextField's controller with a selection of 0,0, then the TextField wouldn't show the selection menu before any text was entered.

TextField(
  controller: TextEditingController.fromValue(
    TextEditingValue(
      selection: TextEditingSelection(baseOffset: 0, extentOffset: 0),
    ),
  ),
),

The problem is that when the user focuses the field, RenderEditable tries to set the selection to 0,0, but it sees that it already is 0,0 and thinks nothing has changed. EditableText is not informed that anything happened, and the selection menu is not created. Usually, selection would be -1,-1 and this would work fine.

This PR considers this situation to be a selection change, so the field will be focused and the selection menu can be shown.

Related Issues

Closes #37798

Tests

• Test that a long press in a 0,0 field successfully shows the selection menu.