await timelinesummary to file (#60774)

dev/benchmarks/complex_layout/test_driver/scroll_perf_test.dart

@@ -50,8 +50,8 @@ void main() {
       });
 
       final TimelineSummary summary = TimelineSummary.summarize(timeline);
-      summary.writeSummaryToFile(summaryName, pretty: true);
-      summary.writeTimelineToFile(summaryName, pretty: true);
+      await summary.writeSummaryToFile(summaryName, pretty: true);
+      await summary.writeTimelineToFile(summaryName, pretty: true);
     }
 
     test('complex_layout_scroll_perf', () async {

dev/benchmarks/macrobenchmarks/test_driver/util.dart

@@ -53,10 +53,10 @@ void macroPerfTest(
       await durationFuture;
     });
 
-    final TimelineSummary summary = TimelineSummary.summarize(timeline);
-    summary.writeSummaryToFile(testName, pretty: true);
-    summary.writeTimelineToFile(testName, pretty: true);
-
     driver.close();
+
+    final TimelineSummary summary = TimelineSummary.summarize(timeline);
+    await summary.writeSummaryToFile(testName, pretty: true);
+    await summary.writeTimelineToFile(testName, pretty: true);
   }, timeout: Timeout(timeout));
 }

dev/benchmarks/platform_views_layout/test_driver/scroll_perf_test.dart

@@ -50,8 +50,8 @@ void main() {
       });
 
       final TimelineSummary summary = TimelineSummary.summarize(timeline);
-      summary.writeSummaryToFile(summaryName, pretty: true);
-      summary.writeTimelineToFile(summaryName, pretty: true);
+      await summary.writeSummaryToFile(summaryName, pretty: true);
+      await summary.writeTimelineToFile(summaryName, pretty: true);
     }
 
     test('platform_views_scroll_perf', () async {

dev/benchmarks/test_apps/stocks/test_driver/scroll_perf_test.dart

@@ -40,8 +40,8 @@ void main() {
       });
 
       final TimelineSummary summary = TimelineSummary.summarize(timeline);
-      summary.writeSummaryToFile('stocks_scroll_perf', pretty: true);
-      summary.writeTimelineToFile('stocks_scroll_perf', pretty: true);
+      await summary.writeSummaryToFile('stocks_scroll_perf', pretty: true);
+      await summary.writeTimelineToFile('stocks_scroll_perf', pretty: true);
     });
   });
 }

dev/integration_tests/flutter_gallery/test_driver/scroll_perf_test.dart

@@ -43,9 +43,9 @@ void main() {
         }
       });
 
-      TimelineSummary.summarize(timeline)
-        ..writeSummaryToFile('home_scroll_perf', pretty: true)
-        ..writeTimelineToFile('home_scroll_perf', pretty: true);
+      final TimelineSummary summary = TimelineSummary.summarize(timeline);
+      await summary.writeSummaryToFile('home_scroll_perf', pretty: true);
+      await summary.writeTimelineToFile('home_scroll_perf', pretty: true);
     });
   });
 }