[cfe] Migrate tools that do not depend on package:vm

Change-Id: I1cc29637bcc01880d56963447c1d34028e6c8504
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/207139
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>

Author: johnniwinther

pkg/front_end/test/simple_stats.dart

@@ -2,14 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
-// @dart = 2.9
-
 import 'dart:math' as math;
 
 class SimpleTTestStat {
   static TTestResult ttest<E extends num>(List<E> a, List<E> b) {
-    E aSum = a.reduce((value, element) => (value + element));
-    E bSum = b.reduce((value, element) => (value + element));
+    E aSum = a.reduce((value, element) => (value + element) as E);
+    E bSum = b.reduce((value, element) => (value + element) as E);
     int aCount = a.length;
     int bCount = b.length;
     double aMean = aSum / aCount;
@@ -37,7 +35,7 @@ class SimpleTTestStat {
   }
 
   static double variance<E extends num>(List<E> data) {
-    E sum = data.reduce((value, element) => (value + element));
+    E sum = data.reduce((value, element) => (value + element) as E);
     int count = data.length;
     double average = sum / count;
 

pkg/front_end/tool/_fasta/log_analyzer.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import 'dart:convert' show jsonDecode, jsonEncode;
 
 import 'dart:io';

pkg/front_end/tool/fasta.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import 'dart:io';
 
 import '../test/utils/io_utils.dart' show computeRepoDir;
@@ -95,7 +93,7 @@ main(List<String> args) async {
   exitCode = await process.exitCode;
 }
 
-void stop(String message) {
+Never stop(String message) {
   stderr.write(message);
   exit(2);
 }

pkg/front_end/tool/smoke_test_quick.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import 'dart:io' show Platform, Process, ProcessResult, exitCode;
 
 import '../test/utils/io_utils.dart' show computeRepoDir;

pkg/front_end/tool/stat_on_dash_v.dart

@@ -2,13 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import "dart:io";
 
 import "../test/simple_stats.dart";
 
-void usage([String extraMessage]) {
+void usage([String? extraMessage]) {
   print("Usage:");
   print("On Linux via bash you can do something like");
   print("dart pkg/front_end/tool/stat_on_dash_v.dart \ "
@@ -68,12 +66,12 @@ main(List<String> args) {
 
   bool printedAnything = false;
   for (String part in data.keys) {
-    Map<String, List<int>> partData = data[part];
-    List<int> prevRuntimes;
-    String prevGroup;
+    Map<String, List<int>> partData = data[part]!;
+    List<int>? prevRuntimes;
+    String? prevGroup;
     bool printed = false;
     for (String group in allGroups) {
-      List<int> runtimes = partData[group];
+      List<int>? runtimes = partData[group];
       if (runtimes == null) {
         // Fake it to be a small list of 0s.
         runtimes = new List<int>.filled(5, 0);
@@ -101,7 +99,8 @@ main(List<String> args) {
             leastConfidentChange = result.diff - result.confidence;
           }
 
-          combinedChange["$prevGroup => $group"] += leastConfidentChange;
+          combinedChange["$prevGroup => $group"] =
+              combinedChange["$prevGroup => $group"]! + leastConfidentChange;
         }
       }
       prevRuntimes = runtimes;
@@ -115,7 +114,7 @@ main(List<String> args) {
   if (printedAnything) {
     for (String part in combinedChange.keys) {
       print("Combined least change for $part: "
-          "${combinedChange[part].toStringAsFixed(2)} ms.");
+          "${combinedChange[part]!.toStringAsFixed(2)} ms.");
     }
   } else {
     print("Nothing significant found.");

pkg/front_end/tool/update_all.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import 'package:_fe_analyzer_shared/src/testing/id_testing.dart' as id;
 import 'update_expectations.dart' as expectations;
 

pkg/front_end/tool/update_expectations.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.9
-
 import 'fasta.dart' as fasta;
 
 const List<String> standardSuites = <String>[
@@ -19,7 +17,7 @@ const List<String> specialSuites = <String>[
   'incremental',
 ];
 
-Future<void> runStandardSuites([List<String> args]) async {
+Future<void> runStandardSuites([List<String>? args]) async {
   // Assert that 'strong' is the first suite - we use the assumption below.
   assert(standardSuites.first == 'weak', "Suite 'weak' most be the first.");
   bool first = true;