[Issue 20134] autodecode should use replacementDchar rather than throwing on invalid

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20134

Iain Buclaw <ibuclaw at gdcproject.org> changed:

           What    |Removed                     |Added
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           Priority|P1                          |P4

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