Issue Link

#148692

Target

stable

PR Link

#149208

Changelog Description

Fixes an EditableText crash that happens with a custom TextEditingController which only implements the TextEditingController interface.

Impacted Users

Apps that uses a custom TextEditingController that implements TextEditingController

Impact Description

Production apps crash if the user gives an EditableText a custom TextEditingControllor class that implements TextEditingControllor.

Workaround

The crash does not happen if the user extends TextEditingControllor, but it's not always desirable / feasible. The class could be already extending a different base class.

Risk

low

Test Coverage

yes

Validation Steps

Run the test in the PR, or follow the repro steps in #148692