Fix issue 12288: a getter also returns something.

sdk/lib/_internal/compiler/implementation/types/container_tracer.dart

Index: sdk/lib/_internal/compiler/implementation/types/container_tracer.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/types/container_tracer.dart	(revision 26049)
+++ sdk/lib/_internal/compiler/implementation/types/container_tracer.dart	(working copy)
@@ -320,9 +320,7 @@
   bool couldBeTheList(resolved) {
     if (resolved is Selector) {
       return escapingElements.any((e) {
-        return e.isInstanceMember()
-            && (e.isField() || e.isFunction())
-            && resolved.applies(e, compiler);
+        return e.isInstanceMember() && resolved.applies(e, compiler);
       });
     } else if (resolved is Node) {
       return analyzedNode == resolved;