Fix for subscribing for notifications for files in packages.

pkg/analysis_server/lib/src/domain_execution.dart

 // Copyright (c) 2014, 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.
 
 library domain.execution;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/analysis_server.dart';
@@ skipping 96 matching lines @@
         return new Response.invalidParameter(request, 'file',
             'Either file or uri must be provided, but not both');
       }
       Resource resource = server.resourceProvider.getResource(file);
       if (!resource.exists) {
         return new Response.invalidParameter(request, 'file', 'Must exist');
       } else if (resource is! File) {
         return new Response.invalidParameter(
             request, 'file', 'Must not refer to a directory');
       }
-      Source source = server.getSource(file);
+      ContextSourcePair contextSource = server.getContextSourcePair(file);
+      Source source = contextSource.source;
       uri = context.sourceFactory.restoreUri(source).toString();
       return new ExecutionMapUriResult(uri: uri).toResponse(request.id);
     } else if (uri != null) {
       Source source = context.sourceFactory.forUri(uri);
       if (source == null) {
         return new Response.invalidParameter(request, 'uri', 'Invalid URI');
       }
       file = source.fullName;
       return new ExecutionMapUriResult(file: file).toResponse(request.id);
     }
@@ skipping 22 matching lines @@
   }
 
   void _fileAnalyzed(ChangeNotice notice) {
     ServerPerformanceStatistics.executionNotifications.makeCurrentWhile(() {
       Source source = notice.source;
       String filePath = source.fullName;
       if (!_isInAnalysisRoot(filePath)) {
         return;
       }
       AnalysisContext context = server.getAnalysisContext(filePath);
+      if (context == null) {
+        return;
+      }
       if (AnalysisEngine.isDartFileName(filePath)) {
         ExecutableKind kind = ExecutableKind.NOT_EXECUTABLE;
         if (context.isClientLibrary(source)) {
           kind = ExecutableKind.CLIENT;
           if (context.isServerLibrary(source)) {
             kind = ExecutableKind.EITHER;
           }
         } else if (context.isServerLibrary(source)) {
           kind = ExecutableKind.SERVER;
         }
@@ skipping 55 matching lines @@
     if (_isInAnalysisRoot(filePath)) {
       server.sendNotification(
           new ExecutionLaunchDataParams(filePath, kind: kind).toNotification());
     }
   }
 
   static List<String> _getFullNames(List<Source> sources) {
     return sources.map((Source source) => source.fullName).toList();
   }
 }