PR Summary

Need to fix in two places to correctly calculate length of string in buffer cells if the string contains double wide chars. When used interactively, the console host does the calculation, so need to make a method that was only used on Windows available for all platforms and use it to calculate length in buffer cells. When formatting goes through Out-String, then it uses the default length calculation in line output so that needed to use the same method. Since the code is in two different assemblies, there is two copies of the same code.

PR Context

Fix #11232

PR Checklist

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