Fixing exception during sayAll on desktop (#14092)
Fixes #14090.
Summary of the issue:
Getting rid of exception when trying to sayall on desktop.
Description of user facing changes
n/a
Description of development approach
Exception happens when trying to dispose of _TextReader object, that failed to initialize its textInfo.
Initializing textInfo (reader field) to None to avoid this.
Testing strategy:
Tested manually as described in #14090.
Also tested manually that sayall still works in text documents and in HTML tables.
