remove type suggestion when interpolation completion

pkg/analysis_server/lib/src/services/completion/dart_completion_cache.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.dart.cache;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/protocol_server.dart'
@@ skipping 287 matching lines @@
     CompletionSuggestion suggestion =
         createSuggestion(element, relevance: relevance);
 
     if (element is ExecutableElement) {
       DartType returnType = element.returnType;
       if (returnType != null && returnType.isVoid) {
         importedVoidReturnSuggestions.add(suggestion);
       } else {
         otherImportedSuggestions.add(suggestion);
       }
+    } else if (element is FunctionTypeAliasElement) {
+      importedTypeSuggestions.add(suggestion);
     } else if (element is ClassElement) {
       importedTypeSuggestions.add(suggestion);
       _addConstructorSuggestions(element, relevance);
     } else {
       otherImportedSuggestions.add(suggestion);
     }
     _importedCompletions.add(suggestion.completion);
   }
 
   /**
@@ skipping 58 matching lines @@
   @override
   void visitFunctionTypeAliasElement(FunctionTypeAliasElement element) {
     cache._addSuggestion(element, DART_RELEVANCE_DEFAULT);
   }
 
   @override
   void visitTopLevelVariableElement(TopLevelVariableElement element) {
     cache._addSuggestion(element, DART_RELEVANCE_DEFAULT);
   }
 }