fix code completion invocation on getter

pkg/analysis_server/lib/src/services/completion/invocation_computer.dart

Index: pkg/analysis_server/lib/src/services/completion/invocation_computer.dart
diff --git a/pkg/analysis_server/lib/src/services/completion/invocation_computer.dart b/pkg/analysis_server/lib/src/services/completion/invocation_computer.dart
index 0dc731937dd456761142f0f7a55c95ca5505c090..f6e68d5e2007a9c96ceff03b07825df6eef573d2 100644
--- a/pkg/analysis_server/lib/src/services/completion/invocation_computer.dart
+++ b/pkg/analysis_server/lib/src/services/completion/invocation_computer.dart
@@ -149,15 +149,15 @@ class _PrefixedIdentifierSuggestionBuilder extends
     if (node is PrefixedIdentifier) {
       SimpleIdentifier prefix = node.prefix;
       if (prefix != null) {
-        if (prefix.propagatedType != null) {
+        Element element = prefix.bestElement;
+        DartType type = prefix.bestType;
+        if (element is! ClassElement && type != null && !type.isDynamic) {
           InterfaceTypeSuggestionBuilder.suggestionsFor(
               request,
-              prefix.propagatedType);
-        } else {
-          Element element = prefix.bestElement;
-          if (element != null) {
-            return element.accept(this);
-          }
+              type);
+          return new Future.value(true);
+        } else if (element != null) {
+          return element.accept(this);
         }
       }
     }