include library prefix completions given trailing local method invocation

pkg/analysis_server/test/services/completion/invocation_computer_test.dart

Index: pkg/analysis_server/test/services/completion/invocation_computer_test.dart
diff --git a/pkg/analysis_server/test/services/completion/invocation_computer_test.dart b/pkg/analysis_server/test/services/completion/invocation_computer_test.dart
index 7f4c2091f3895690a813a9e297da44a5af152c49..16fcb6ec9ff0c3ee63bb66d97b57712b54f3fc33 100644
--- a/pkg/analysis_server/test/services/completion/invocation_computer_test.dart
+++ b/pkg/analysis_server/test/services/completion/invocation_computer_test.dart
@@ -137,6 +137,22 @@ void f(C<int> c) {
     });
   }
 
+  test_libraryPrefix() {
+    // SimpleIdentifier  PrefixedIdentifier  ExpressionStatement
+    addTestSource('import "dart:async" as bar; foo() {bar.^}');
+    return computeFull((bool result) {
+      assertSuggestClass('Future');
+    });
+  }
+
+  test_libraryPrefix2() {
+    // SimpleIdentifier  MethodInvocation  ExpressionStatement
+    addTestSource('import "dart:async" as bar; foo() {bar.^ print("f")}');
+    return computeFull((bool result) {
+      assertSuggestClass('Future');
+    });
+  }
+
   test_local() {
     addTestSource('foo() {String x = "bar"; x.^}');
     return computeFull((bool result) {