Change getRange to sublist. Make getRange deprecated.

sdk/lib/io/http_parser.dart

Index: sdk/lib/io/http_parser.dart
diff --git a/sdk/lib/io/http_parser.dart b/sdk/lib/io/http_parser.dart
index cecd6320d7a1b3be248468670bcb5ec15d6507ff..c008f349987e5d0e4026e2e9c4ce9cac4d7b8079 100644
--- a/sdk/lib/io/http_parser.dart
+++ b/sdk/lib/io/http_parser.dart
@@ -795,7 +795,7 @@ class _HttpParser
   List<int> readUnparsedData() {
     if (_buffer == null) return null;
     if (_index == _buffer.length) return null;
-    var result = _buffer.getRange(_index, _buffer.length - _index);
+    var result = _buffer.sublist(_index);
     _releaseBuffer();
     return result;
   }