Do not run analyzer benchmarks in checked mode.

Change-Id: Ib591a981d29ae671c6c6ea3b4f1e64e098607a5a
Reviewed-on: https://dart-review.googlesource.com/54230
Reviewed-by: Jonas Termansen <sortie@google.com>
Reviewed-by: Devon Carew <devoncarew@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
diff --git a/pkg/analysis_server/benchmark/perf/memory_tests.dart b/pkg/analysis_server/benchmark/perf/memory_tests.dart
index ea4b3ba..2d9e01e 100644
--- a/pkg/analysis_server/benchmark/perf/memory_tests.dart
+++ b/pkg/analysis_server/benchmark/perf/memory_tests.dart
@@ -77,6 +77,7 @@
     return startServer(
       servicesPort: vmServicePort,
       cfe: useCFE,
+      checked: false,
     ).then((_) {
       server.listenToOutput(dispatchNotification);
       server.exitCode.then((_) {