Retire digit-separators experiment in SDK 3.7.

Change-Id: I6a37665fa76059f665b52844e4a9784dca6224b0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/400381
Reviewed-by: Alexander Thomas <athom@google.com>
Commit-Queue: Lasse Nielsen <lrn@google.com>

pkg/_fe_analyzer_shared/lib/src/experiments/flags.dart

@@ -55,7 +55,7 @@ enum ExperimentalFlag {
   digitSeparators(
       name: 'digit-separators',
       isEnabledByDefault: true,
-      isExpired: false,
+      isExpired: true,
       experimentEnabledVersion: const Version(3, 6),
       experimentReleasedVersion: const Version(3, 6)),
 

pkg/analyzer/lib/src/dart/analysis/experiments.g.dart

@@ -710,7 +710,7 @@ class IsExpired {
   static const bool control_flow_collections = true;
 
   /// Expiration status of the experiment "digit-separators"
-  static const bool digit_separators = false;
+  static const bool digit_separators = true;
 
   /// Expiration status of the experiment "enhanced-enums"
   static const bool enhanced_enums = true;

pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart

@@ -110,7 +110,7 @@ class ExperimentalFlag {
   static const ExperimentalFlag digitSeparators = const ExperimentalFlag(
       name: 'digit-separators',
       isEnabledByDefault: true,
-      isExpired: false,
+      isExpired: true,
       enabledVersion: const Version(3, 6),
       experimentEnabledVersion: const Version(3, 6),
       experimentReleasedVersion: const Version(3, 6));

pkg/front_end/messages.yaml

@@ -1782,7 +1782,6 @@ UnexpectedSeparatorInNumber:
   problemMessage: "Digit separators ('_') in a number literal can only be placed between two digits."
   correctionMessage: "Try removing the '_'."
   analyzerCode: UNEXPECTED_SEPARATOR_IN_NUMBER
-  experiments: digit-separators
   expression:
     - '123_'
     - '1.23_'

pkg/front_end/testcases/coverage/digit-separators/folder.options

@@ -1 +0,0 @@
---enable-experiment=digit-separators

tests/language/number/separators_error_test.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.
 
-// SharedOptions=--enable-experiment=digit-separators
-
 import "package:expect/expect.dart";
 
 main() {

tests/language/number/separators_test.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.
 
-// SharedOptions=--enable-experiment=digit-separators
-
 import "package:expect/expect.dart";
 import 'package:expect/variations.dart' as v;
 

tools/experimental_features.yaml

@@ -195,6 +195,7 @@ features:
         print('feature enabled');
       }
     help: "Number literals with digit separators."
+    expired: true
 
   inference-update-3: # See https://github.com/dart-lang/language/issues/1618
     enabledIn: '3.4.0'