Fixes leak of native File objects.

sdk/lib/_internal/js_runtime/lib/io_patch.dart

Index: sdk/lib/_internal/js_runtime/lib/io_patch.dart
diff --git a/sdk/lib/_internal/js_runtime/lib/io_patch.dart b/sdk/lib/_internal/js_runtime/lib/io_patch.dart
index e4038448bfb9637448f6f65e8241eb76b598e1bf..51e00786e6f0b38623ae56c4086aae1beedf0b3e 100644
--- a/sdk/lib/_internal/js_runtime/lib/io_patch.dart
+++ b/sdk/lib/_internal/js_runtime/lib/io_patch.dart
@@ -135,58 +135,10 @@ class _File {
 }
 
 @patch
-class _RandomAccessFile {
+class _RandomAccessFileOps {
   @patch
-  static int _close(int id) {
-    throw new UnsupportedError("RandomAccessFile._close");
-  }
-  @patch
-  static int _getFD(int id) {
-    throw new UnsupportedError("RandomAccessFile._getFD");
-  }
-  @patch
-  static _readByte(int id) {
-    throw new UnsupportedError("RandomAccessFile._readByte");
-  }
-  @patch
-  static _read(int id, int bytes) {
-    throw new UnsupportedError("RandomAccessFile._read");
-  }
-  @patch
-  static _readInto(int id, List<int> buffer, int start, int end) {
-    throw new UnsupportedError("RandomAccessFile._readInto");
-  }
-  @patch
-  static _writeByte(int id, int value) {
-    throw new UnsupportedError("RandomAccessFile._writeByte");
-  }
-  @patch
-  static _writeFrom(int id, List<int> buffer, int start, int end) {
-    throw new UnsupportedError("RandomAccessFile._writeFrom");
-  }
-  @patch
-  static _position(int id) {
-    throw new UnsupportedError("RandomAccessFile._position");
-  }
-  @patch
-  static _setPosition(int id, int position) {
-    throw new UnsupportedError("RandomAccessFile._setPosition");
-  }
-  @patch
-  static _truncate(int id, int length) {
-    throw new UnsupportedError("RandomAccessFile._truncate");
-  }
-  @patch
-  static _length(int id) {
-    throw new UnsupportedError("RandomAccessFile._length");
-  }
-  @patch
-  static _flush(int id) {
-    throw new UnsupportedError("RandomAccessFile._flush");
-  }
-  @patch
-  static _lock(int id, int lock, int start, int end) {
-    throw new UnsupportedError("RandomAccessFile._lock");
+  factory _RandomAccessFileOps(int pointer) {
+    throw new UnsupportedError("RandomAccessFile");
   }
 }