anchor.diff:      late FlutterDriver driver;
   
       setUpAll(() async {
  +      // Turn off any accessibility services that may be running. The purpose of
  +      // the test is to measure the time it takes to create the initial
  +      // semantics tree in isolation. If accessibility services are on, the
  +      // semantics tree gets generated during the first frame and we can't
  +      // measure it in isolation.
  +      final Process run = await Process.start(_adbPath(), const <String>[
  +        'shell',
  +        'settings',
  +        'put',
  +        'secure',
  +        'enabled_accessibility_services',
  +        'null',
  +      ]);
  +      await run.exitCode;
  +
         driver = await FlutterDriver.connect(printCommunication: true);
       });
   
  
positive.code:     }, timeout: Timeout.none);
    });
  }
  
negative.code:       await driver.forceGC();
  
        final Timeline timeline = await driver.traceAction(() async {
          expect(
            await driver.setSemantics(true),
            isTrue,
            reason: 'Could not toggle semantics to on because semantics were already '
                    'on, but the test needs to toggle semantics to measure the initial '
                    'semantics tree generation in isolation.'
          );
        });
  
        final Iterable<TimelineEvent>? semanticsEvents = timeline.events?.where((TimelineEvent event) => event.name == 'SEMANTICS');
  