Fix some strong mode issues in the core libraries.

R=vsm@google.com

Review-Url: https://codereview.chromium.org/2764943002 .

CHANGELOG.md

@@ -1,3 +1,9 @@
+## 1.24.0
+
+### Core library changes
+* `dart:convert`
+  * Removed deprecated `ChunkedConverter` class.
+
 ## 1.23.0
 
 ### Language

sdk/lib/async/stream.dart

@@ -1314,8 +1314,7 @@ abstract class Stream<T> {
         // should be inferred.
         var registeredOnTimeout =
             zone.registerUnaryCallback<dynamic, EventSink<T>>(onTimeout);
-        _ControllerEventSinkWrapper wrapper =
-            new _ControllerEventSinkWrapper(null);
+        var wrapper = new _ControllerEventSinkWrapper<T>(null);
         timeout = () {
           wrapper._sink = controller; // Only valid during call.
           zone.runUnaryGuarded(registeredOnTimeout, wrapper);

sdk/lib/collection/queue.dart

@@ -94,7 +94,7 @@ abstract class Queue<E> implements EfficientLengthIterable<E> {
   void clear();
 }
 
-class _DoubleLink<Link extends _DoubleLink> {
+class _DoubleLink<Link extends _DoubleLink<Link>> {
   Link _previousLink;
   Link _nextLink;
 

sdk/lib/convert/ascii.dart

@@ -69,8 +69,7 @@ class AsciiCodec extends Encoding {
 
 // Superclass for [AsciiEncoder] and [Latin1Encoder].
 // Generalizes common operations that only differ by a mask;
-class _UnicodeSubsetEncoder extends Converter<String, List<int>>
-    implements ChunkedConverter<String, List<int>, String, List<int>> {
+class _UnicodeSubsetEncoder extends Converter<String, List<int>> {
   final int _subsetMask;
 
   const _UnicodeSubsetEncoder(this._subsetMask);
@@ -155,8 +154,7 @@ class _UnicodeSubsetEncoderSink extends StringConversionSinkBase {
  * This class converts Latin-1 bytes (lists of unsigned 8-bit integers)
  * to a string.
  */
-abstract class _UnicodeSubsetDecoder extends Converter<List<int>, String>
-    implements ChunkedConverter<List<int>, String, List<int>, String> {
+abstract class _UnicodeSubsetDecoder extends Converter<List<int>, String> {
   final bool _allowInvalid;
   final int _subsetMask;
 

sdk/lib/convert/base64.dart

@@ -204,8 +204,7 @@ class Base64Codec extends Codec<List<int>, String> {
  *
  * The results are ASCII strings using a restricted alphabet.
  */
-class Base64Encoder extends Converter<List<int>, String>
-    implements ChunkedConverter<List<int>, String, List<int>, String> {
+class Base64Encoder extends Converter<List<int>, String> {
 
   final bool _urlSafe;
 
@@ -476,8 +475,7 @@ class _Utf8Base64EncoderSink extends _Base64EncoderSink {
  *
  * The encoding is required to be properly padded.
  */
-class Base64Decoder extends Converter<String, List<int>>
-    implements ChunkedConverter<String, List<int>, String, List<int>> {
+class Base64Decoder extends Converter<String, List<int>> {
 
   const Base64Decoder();
 

sdk/lib/convert/chunked_conversion.dart

@@ -6,16 +6,6 @@ part of dart.convert;
 
 typedef void _ChunkedConversionCallback<T>(T accumulated);
 
-/// This class is deprecated. Extend [Converter] directly.
-@deprecated
-abstract class ChunkedConverter<S, T, S2, T2> extends Converter<S, T> {
-  const ChunkedConverter() : super();
-
-  dynamic bind(dynamic other) => super.bind(other);
-  dynamic startChunkedConversion(dynamic sink) =>
-      super.startChunkedConversion(sink);
-}
-
 /**
  * A [ChunkedConversionSink] is used to transmit data more efficiently between
  * two converters during chunked conversions.

sdk/lib/convert/converter.dart

@@ -50,8 +50,7 @@ abstract class Converter<S, T> implements StreamTransformer<S, T> {
  *
  * For a non-chunked conversion converts the input in sequence.
  */
-class _FusedConverter<S, M, T> extends Converter<S, T>
-    implements ChunkedConverter<S, T, S, T> {
+class _FusedConverter<S, M, T> extends Converter<S, T> {
   final Converter<S, M> _first;
   final Converter<M, T> _second;
 

sdk/lib/convert/html_escape.dart

@@ -151,8 +151,7 @@ class HtmlEscapeMode {
  * found to be easier to read if greater-than is also escaped whenever
  * less-than is.
  */
-class HtmlEscape extends Converter<String, String>
-    implements ChunkedConverter<String, String, String, String> {
+class HtmlEscape extends Converter<String, String> {
   /** The [HtmlEscapeMode] used by the converter. */
   final HtmlEscapeMode mode;
 

sdk/lib/convert/json.dart

@@ -156,8 +156,7 @@ class JsonCodec extends Codec<Object, String> {
 /**
  * This class converts JSON objects to strings.
  */
-class JsonEncoder extends Converter<Object, String>
-    implements ChunkedConverter<Object, String, Object, String> {
+class JsonEncoder extends Converter<Object, String> {
   /**
    * The string used for indention.
    *
@@ -283,8 +282,7 @@ class JsonEncoder extends Converter<Object, String>
  * a JSON string, and then UTF-8 encoding the string, but without
  * creating an intermediate string.
  */
-class JsonUtf8Encoder extends Converter<Object, List<int>>
-    implements ChunkedConverter<Object, List<int>, Object, List<int>> {
+class JsonUtf8Encoder extends Converter<Object, List<int>> {
   /** Default buffer size used by the JSON-to-UTF-8 encoder. */
   static const int DEFAULT_BUFFER_SIZE = 256;
   /** Indentation used in pretty-print mode, `null` if not pretty. */
@@ -468,8 +466,7 @@ class _JsonUtf8EncoderSink extends ChunkedConversionSink<Object> {
 /**
  * This class parses JSON strings and builds the corresponding objects.
  */
-class JsonDecoder extends Converter<String, Object>
-    implements ChunkedConverter<String, Object, String, Object> {
+class JsonDecoder extends Converter<String, Object> {
   final _Reviver _reviver;
   /**
    * Constructs a new JsonDecoder.

sdk/lib/convert/line_splitter.dart

@@ -20,8 +20,7 @@ const int _CR = 13;
 
 class LineSplitter extends Converter<String, List<String>> /*=Object*/
     implements
-        ChunkedConverter<String, List<String>, String, String>
-/*=StreamTransformer<String, String>*/ {
+        Object/*=StreamTransformer<String, String>*/ {
   const LineSplitter();
 
   /// Split [lines] into individual lines.

sdk/lib/convert/utf.dart

@@ -76,8 +76,7 @@ class Utf8Codec extends Encoding {
  * This class converts strings to their UTF-8 code units (a list of
  * unsigned 8-bit integers).
  */
-class Utf8Encoder extends Converter<String, List<int>>
-    implements ChunkedConverter<String, List<int>, String, List<int>> {
+class Utf8Encoder extends Converter<String, List<int>> {
   const Utf8Encoder();
 
   /**
@@ -303,8 +302,7 @@ class _Utf8EncoderSink extends _Utf8Encoder with StringConversionSinkMixin {
  * This class converts UTF-8 code units (lists of unsigned 8-bit integers)
  * to a string.
  */
-class Utf8Decoder extends Converter<List<int>, String>
-    implements ChunkedConverter<List<int>, String, List<int>, String> {
+class Utf8Decoder extends Converter<List<int>, String> {
   final bool _allowMalformed;
 
   /**

sdk/lib/io/data_transformer.dart

@@ -292,8 +292,7 @@ class GZipCodec extends Codec<List<int>, List<int>> {
  * The [ZLibEncoder] encoder is used by [ZLibCodec] and [GZipCodec] to compress
  * data.
  */
-class ZLibEncoder extends Converter<List<int>, List<int>>
-    implements ChunkedConverter<List<int>, List<int>, List<int>, List<int>> {
+class ZLibEncoder extends Converter<List<int>, List<int>> {
   /**
    * When true, `GZip` frames will be added to the compressed data.
    */

sdk/lib/io/file_impl.dart

@@ -199,7 +199,7 @@ class _FileStreamConsumer extends StreamConsumer<List<int>> {
   }
 
   Future<File> close() =>
-      _openFuture.then<File>((openedFile) => openedFile.close());
+      _openFuture.then((openedFile) => openedFile.close()).then((_) => _file);
 }
 
 // Class for encapsulating the native implementation of files.
@@ -556,7 +556,7 @@ class _File extends FileSystemEntity implements File {
   Future<File> writeAsBytes(List<int> bytes,
       {FileMode mode: FileMode.WRITE, bool flush: false}) {
     return open(mode: mode).then((file) {
-      return file.writeFrom(bytes, 0, bytes.length).then((_) {
+      return file.writeFrom(bytes, 0, bytes.length).then<File>((_) {
         if (flush) return file.flush().then((_) => this);
         return this;
       }).whenComplete(file.close);

sdk/lib/io/string_transformer.dart

@@ -42,8 +42,7 @@ class SystemEncoding extends Encoding {
   }
 }
 
-class _WindowsCodePageEncoder extends Converter<String, List<int>>
-    implements ChunkedConverter<String, List<int>, String, List<int>> {
+class _WindowsCodePageEncoder extends Converter<String, List<int>> {
   const _WindowsCodePageEncoder();
 
   List<int> convert(String input) {
@@ -93,8 +92,7 @@ class _WindowsCodePageEncoderSink extends StringConversionSinkBase {
   }
 }
 
-class _WindowsCodePageDecoder extends Converter<List<int>, String>
-    implements ChunkedConverter<List<int>, String, List<int>, String> {
+class _WindowsCodePageDecoder extends Converter<List<int>, String> {
   const _WindowsCodePageDecoder();
 
   String convert(List<int> input) {