only suggest types when completing from a library prefix in parameter list

pkg/analysis_server/lib/src/services/completion/invocation_computer.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.computer.dart.invocation;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
 import 'package:analysis_server/src/services/completion/local_declaration_visitor.dart';
@@ skipping 305 matching lines @@
     //TODO (danrubel) reimplement to use prefixElement.importedLibraries
     // once that accessor is implemented and available in Dart
     bool modified = false;
     // Find the import directive with the given prefix
     for (Directive directive in request.unit.directives) {
       if (directive is ImportDirective) {
         if (directive.prefix != null) {
           if (directive.prefix.name == element.name) {
             // Suggest elements from the imported library
             LibraryElement library = directive.uriElement;
-            LibraryElementSuggestionBuilder.suggestionsFor(
-                request, CompletionSuggestionKind.INVOCATION, library);
+            LibraryElementSuggestionBuilder.suggestionsFor(request,
+                CompletionSuggestionKind.INVOCATION, library,
+                request.target.containingNode.parent is TypeName);
             modified = true;
           }
         }
       }
     }
     return new Future.value(modified);
   }
 
   @override
   Future<bool> visitPropertyAccessorElement(PropertyAccessorElement element) {
     if (element != null) {
       PropertyInducingElement elemVar = element.variable;
       if (elemVar != null) {
         InterfaceTypeSuggestionBuilder.suggestionsFor(request, elemVar.type);
       }
       return new Future.value(true);
     }
     return new Future.value(false);
   }
 
   @override
   Future<bool> visitVariableElement(VariableElement element) {
     InterfaceTypeSuggestionBuilder.suggestionsFor(request, element.type);
     return new Future.value(true);
   }
 }