Do not suppress implicit constructors that need a super call.

lib/runtime/dart/convert.js

 var convert;
 (function(exports) {
   'use strict';
   let ASCII = dart.const(new AsciiCodec());
   let _ASCII_MASK = 127;
   let _allowInvalid = Symbol('_allowInvalid');
   let Codec$ = dart.generic(function(S, T) {
     class Codec extends core.Object {
       Codec() {
       }
@@ skipping 243 matching lines @@
     withCallback(callback) {
       return new _ByteCallbackSink(callback);
     }
     from(sink) {
       return new _ByteAdapterSink(sink);
     }
   }
   dart.defineNamedConstructor(ByteConversionSink, 'withCallback');
   dart.defineNamedConstructor(ByteConversionSink, 'from');
   class ByteConversionSinkBase extends ByteConversionSink {
+    ByteConversionSinkBase() {
+      super.ByteConversionSink();
+    }
     addSlice(chunk, start, end, isLast) {
       this.add(chunk[core.$sublist](start, end));
       if (isLast)
         this.close();
     }
   }
   class _ErrorHandlingAsciiDecoderSink extends ByteConversionSinkBase {
     _ErrorHandlingAsciiDecoderSink(utf8Sink) {
       this[_utf8Sink] = utf8Sink;
     }
@@ skipping 2143 matching lines @@
   exports.LineSplitter = LineSplitter;
   exports.StringConversionSink = StringConversionSink;
   exports.ClosableStringSink = ClosableStringSink;
   exports.UNICODE_REPLACEMENT_CHARACTER_RUNE = UNICODE_REPLACEMENT_CHARACTER_RUNE;
   exports.UNICODE_BOM_CHARACTER_RUNE = UNICODE_BOM_CHARACTER_RUNE;
   exports.UTF8 = UTF8;
   exports.Utf8Codec = Utf8Codec;
   exports.Utf8Encoder = Utf8Encoder;
   exports.Utf8Decoder = Utf8Decoder;
 })(convert || (convert = {}));