Revert "Fix updating packages map on reload and add a regression test"

runtime/bin/vmservice/loader.dart

 // Copyright (c) 2015, 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.
 
 part of vmservice_io;
 
 _sanitizeWindowsPath(path) {
   // For Windows we need to massage the paths a bit according to
   // http://blogs.msdn.com/b/ie/archive/2006/12/06/file-uris-in-windows.aspx
   //
@@ skipping 1015 matching lines @@
       break;
     case _Dart_kInitLoader:
       {
         String packageRoot = request[4];
         String packagesFile = request[5];
         String workingDirectory = request[6];
         String rootScript = request[7];
         if (loaderState == null) {
           loaderState = new IsolateLoaderState(isolateId);
           isolateEmbedderData[isolateId] = loaderState;
+          loaderState.init(
+              packageRoot, packagesFile, workingDirectory, rootScript);
         }
-        loaderState.init(
-            packageRoot, packagesFile, workingDirectory, rootScript);
         loaderState.sp = sp;
         assert(isolateEmbedderData[isolateId] == loaderState);
       }
       break;
     case _Dart_kResourceLoad:
       {
         Uri uri = Uri.parse(request[4]);
         _handleResourceRequest(
             loaderState, sp, traceLoading, tag, uri, uri, null);
       }
@@ skipping 101 matching lines @@
         msg[2] = resolvedUri.toString();
         msg[3] = null;
         msg[4] = e.toString();
         sp.send(msg);
       }
       break;
     default:
       _log('Unknown loader request tag=$tag from $isolateId');
   }
 }