Version 0.4.7.3 .

editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/internal/analysis/model/ProjectManagerImpl.java

 /*
  * Copyright 2013 Dart project authors.
  * 
  * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
  * in compliance with the License. You may obtain a copy of the License at
  * 
  * http://www.eclipse.org/legal/epl-v10.html
  * 
  * Unless required by applicable law or agreed to in writing, software distributed under the License
  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
@@ skipping 122 matching lines @@
   public void addProjectListener(ProjectListener listener) {
     synchronized (listeners) {
       if (listener != null && !listeners.contains(listener)) {
         listeners.add(listener);
       }
     }
   }
 
   @Override
   public AnalysisContext getContext(IResource resource) {
+    if (resource == null) {
+      return null;
+    }
     return getProject(resource.getProject()).getContext(resource);
   }
 
   @Override
   public IResource getHtmlFileForLibrary(Source source) {
     AnalysisContext context = getContext(getResource(source));
-    Source[] htmlSource = context.getHtmlFilesReferencing(source);
-    if (htmlSource.length > 0) {
-      return getResource(htmlSource[0]);
+    if (context != null) {
+      Source[] htmlSource = context.getHtmlFilesReferencing(source);
+      if (htmlSource.length > 0) {
+        return getResource(htmlSource[0]);
+      }
     }
     return null;
   }
 
   @Override
   public DartIgnoreManager getIgnoreManager() {
     return ignoreManager;
   }
 
   @Override
@@ skipping 278 matching lines @@
   private void removeProject(IProject projectResource) {
     Project result;
     synchronized (projects) {
       result = projects.remove(projectResource);
     }
     if (result != null) {
       result.discardContextsIn(projectResource);
     }
   }
 }