fix code completion import dart exception

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

Index: pkg/analysis_server/test/services/completion/imported_computer_test.dart
diff --git a/pkg/analysis_server/test/services/completion/imported_computer_test.dart b/pkg/analysis_server/test/services/completion/imported_computer_test.dart
index d2c5576ac9e56760356bf814e05908cee5d8da7c..2943da5f1c112d162098d2e63b0a80b6f5c8e5f5 100644
--- a/pkg/analysis_server/test/services/completion/imported_computer_test.dart
+++ b/pkg/analysis_server/test/services/completion/imported_computer_test.dart
@@ -162,6 +162,13 @@ class ImportedTypeComputerTest extends AbstractCompletionTest {
     });
   }
 
+  test_import_dart() {
+    addTestSource('import "dart^"; main() {}');
+    return computeFull().then((_) {
+      assertNotSuggested('T1');
+    });
+  }
+
   test_topLevelVar() {
     addSource('/testA.dart', 'String T1; var _T2;');
     addTestSource('import "/testA.dart"; class C {foo(){^}}');