Revert change to Platform.excutable and add Platform.resolvedExecutable

sdk/lib/_internal/compiler/js_lib/io_patch.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:_js_helper' show patch;
 
 @patch
 class _Directory {
   @patch
   static _current() {
@@ skipping 203 matching lines @@
   }
   @patch
   static _localHostname() {
     throw new UnsupportedError("Platform._localHostname");
   }
   @patch
   static _executable() {
     throw new UnsupportedError("Platform._executable");
   }
   @patch
+  static _resolvedExecutable() {
+    throw new UnsupportedError("Platform._resolvedExecutable");
+  }
+  @patch
   static List<String> _executableArguments() {
     throw new UnsupportedError("Platform._executableArguments");
   }
   @patch
   static String _packageRoot() {
     throw new UnsupportedError("Platform._packageRoot");
   }
   @patch
   static _environment() {
     throw new UnsupportedError("Platform._environment");
@@ skipping 296 matching lines @@
   }
 }
 
 @patch
 class _IOService {
   @patch
   static Future _dispatch(int request, List data) {
     throw new UnsupportedError("_IOService._dispatch");
   }
 }