include exported library namespace in prefixed import suggestions

pkg/analysis_server/lib/src/services/completion/suggestion_builder.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 services.completion.suggestion.builder;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/protocol_server.dart' as protocol;
@@ skipping 458 matching lines @@
   LibraryElementSuggestionBuilder(this.request, this.kind, this.typesOnly);
 
   @override
   visitClassElement(ClassElement element) {
     addSuggestion(element);
   }
 
   @override
   visitCompilationUnitElement(CompilationUnitElement element) {
     element.visitChildren(this);
+    LibraryElement containingLibrary = element.library;
+    if (containingLibrary != null) {
+      for (var lib in containingLibrary.exportedLibraries) {
+        lib.visitChildren(this);
+      }
+    }
   }
 
   @override
   visitElement(Element element) {
     // ignored
   }
 
   @override
   visitFunctionElement(FunctionElement element) {
     if (!typesOnly) {
@@ skipping 155 matching lines @@
    * or `false` if [computeFull] should be called.
    */
   bool computeFast(AstNode node);
 
   /**
    * Return a future that computes the suggestions given a fully resolved AST.
    * The future returns `true` if suggestions were added, else `false`.
    */
   Future<bool> computeFull(AstNode node);
 }