Enable inference in the core libs

test/codegen/expect/dart/convert.js

 var convert;
 (function(exports) {
   'use strict';
   let ASCII = new AsciiCodec();
   let _ASCII_MASK = 127;
   let _allowInvalid = Symbol('_allowInvalid');
   class AsciiCodec extends Encoding {
     AsciiCodec(opt$) {
       let allowInvalid = opt$.allowInvalid === void 0 ? false : opt$.allowInvalid;
       this[_allowInvalid] = allowInvalid;
@@ skipping 234 matching lines @@
     close() {
       return this[_sink].close();
     }
   }
   let _buffer = Symbol('_buffer');
   let _callback = Symbol('_callback');
   let _bufferIndex = Symbol('_bufferIndex');
   let _roundToPowerOf2 = Symbol('_roundToPowerOf2');
   class _ByteCallbackSink extends ByteConversionSinkBase {
     _ByteCallbackSink(callback) {
-      this[_buffer] = new typed_data.Uint8List(dart.as(_ByteCallbackSink._INITIAL_BUFFER_SIZE, core.int));
+      this[_buffer] = new typed_data.Uint8List(_ByteCallbackSink._INITIAL_BUFFER_SIZE);
       this[_callback] = callback;
       this[_bufferIndex] = 0;
       super.ByteConversionSinkBase();
     }
     add(chunk) {
       let freeCount = dart.notNull(this[_buffer].length) - dart.notNull(this[_bufferIndex]);
       if (dart.notNull(chunk.length) > dart.notNull(freeCount)) {
         let oldLength = this[_buffer].length;
         let newLength = dart.notNull(_roundToPowerOf2(dart.notNull(chunk.length) + dart.notNull(oldLength))) * 2;
         let grown = new typed_data.Uint8List(newLength);
@@ skipping 1174 matching lines @@
       this[_chunkedSink] = $_chunkedSink;
       this[_buffer] = new core.StringBuffer();
     }
     close() {
       if (this[_buffer].isNotEmpty)
         this[_flush]();
       this[_chunkedSink].close();
     }
     writeCharCode(charCode) {
       this[_buffer].writeCharCode(charCode);
-      if (this[_buffer].length['>'](_StringConversionSinkAsStringSinkAdapter._MIN_STRING_SIZE))
+      if (dart.notNull(this[_buffer].length) > dart.notNull(_StringConversionSinkAsStringSinkAdapter._MIN_STRING_SIZE))
         this[_flush]();
     }
     write(o) {
       if (this[_buffer].isNotEmpty)
         this[_flush]();
       let str = o.toString();
       this[_chunkedSink].add(o.toString());
     }
     writeln(o) {
       if (o === void 0)
         o = "";
       this[_buffer].writeln(o);
-      if (this[_buffer].length['>'](_StringConversionSinkAsStringSinkAdapter._MIN_STRING_SIZE))
+      if (dart.notNull(this[_buffer].length) > dart.notNull(_StringConversionSinkAsStringSinkAdapter._MIN_STRING_SIZE))
         this[_flush]();
     }
     writeAll(objects, separator) {
       if (separator === void 0)
         separator = "";
       if (this[_buffer].isNotEmpty)
         this[_flush]();
       let iterator = objects.iterator;
       if (!dart.notNull(iterator.moveNext()))
         return;
@@ skipping 213 matching lines @@
     bind(stream) {
       return dart.as(super.bind(stream), async.Stream$(core.List$(core.int)));
     }
   }
   let _Utf8Encoder$withBufferSize = Symbol('_Utf8Encoder$withBufferSize');
   let _createBuffer = Symbol('_createBuffer');
   let _writeSurrogate = Symbol('_writeSurrogate');
   let _fillBuffer = Symbol('_fillBuffer');
   class _Utf8Encoder extends core.Object {
     _Utf8Encoder() {
-      this[_Utf8Encoder$withBufferSize](dart.as(_Utf8Encoder._DEFAULT_BYTE_BUFFER_SIZE, core.int));
+      this[_Utf8Encoder$withBufferSize](_Utf8Encoder._DEFAULT_BYTE_BUFFER_SIZE);
     }
     _Utf8Encoder$withBufferSize(bufferSize) {
       this[_buffer] = _createBuffer(bufferSize);
       this[_carry] = 0;
       this[_bufferIndex] = 0;
     }
     static [_createBuffer](size) {
       return new typed_data.Uint8List(size);
     }
     [_writeSurrogate](leadingSurrogate, nextCodeUnit) {
@@ skipping 613 matching lines @@
   exports.ClosableStringSink = ClosableStringSink;
   exports.StringConversionSinkBase = StringConversionSinkBase;
   exports.StringConversionSinkMixin = StringConversionSinkMixin;
   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 = {}));