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packages/html/lib/src/char_encodings.dart

 /// Decodes bytes using the correct name. See [decodeBytes].
 library char_encodings;
 
 import 'dart:collection';
 import 'package:utf/utf.dart';
 
 // TODO(jmesserly): this function is conspicuously absent from dart:utf.
 /// Returns true if the [bytes] starts with a UTF-8 byte order mark.
 /// Since UTF-8 doesn't have byte order, it's somewhat of a misnomer, but it is
 /// used in HTML to detect the UTF-
@@ skipping 203 matching lines @@
       case 0x9D:
         if (replacementCodepoint == null) {
           throw new ArgumentError(
               "Invalid windows-1252 code point $char at $_offset");
         }
         return replacementCodepoint;
     }
     return char;
   }
 }