/** Initialize this index with information from the user libraries. */
 private boolean indexUserLibraries() {
   boolean librariesIndexed = true;
   try {
     AnalysisServer analysisServer = PackageLibraryManagerProvider.getDefaultAnalysisServer();
     SavedContext savedContext = analysisServer.getSavedContext();
     DartModel model = DartCore.create(ResourcesPlugin.getWorkspace().getRoot());
     for (DartProject project : model.getDartProjects()) {
       for (DartLibrary library : project.getDartLibraries()) {
         CompilationUnit compilationUnit = library.getDefiningCompilationUnit();
         if (compilationUnit == null) {
           continue;
         }
         IResource libraryResource = compilationUnit.getResource();
         if (libraryResource == null) {
           continue;
         }
         IPath libraryLocation = libraryResource.getLocation();
         if (libraryLocation == null) {
           continue;
         }
         File libraryFile = libraryLocation.toFile();
         savedContext.resolve(libraryFile, null);
       }
     }
   } catch (Exception exception) {
     librariesIndexed = false;
     DartCore.logError("Could not index user libraries", exception);
   }
   return librariesIndexed;
 }