diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8d80768..7233909 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -71,6 +71,13 @@
   instance variable, and it brings the implementation behavior in line with
   the specification in all other cases.
 
+### Core libraries
+
+#### `dart:cli`
+
+- The experimental `waitFor` functionality, and the library containing only that
+  function, are now deprecated.
+
 ### Tools
 
 #### Dart command line
@@ -145,11 +152,6 @@
 - Added `void unawaited(Future)` top-level function to deal with the
   `unawaited_futures` lint.
 
-#### `dart:cli`
-
-- The experimental `waitFor` functionality, and the library containing only that
-  function, are now deprecated.
-
 #### `dart:core`
 
 - Introduce `Enum` interface implemented by all `enum` declarations.
diff --git a/pkg/analysis_server/lib/src/analysis_server.dart b/pkg/analysis_server/lib/src/analysis_server.dart
index 97e8276..780bd0b 100644
--- a/pkg/analysis_server/lib/src/analysis_server.dart
+++ b/pkg/analysis_server/lib/src/analysis_server.dart
@@ -4,7 +4,6 @@
 
 import 'dart:async';
 import 'dart:collection';
-import 'dart:core';
 import 'dart:io' as io;
 import 'dart:math' show max;
 
diff --git a/pkg/analysis_server/lib/src/analysis_server_abstract.dart b/pkg/analysis_server/lib/src/analysis_server_abstract.dart
index 5bd16c2..e66a58c 100644
--- a/pkg/analysis_server/lib/src/analysis_server_abstract.dart
+++ b/pkg/analysis_server/lib/src/analysis_server_abstract.dart
@@ -2,7 +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.
 
-import 'dart:core';
 import 'dart:io' as io;
 import 'dart:io';
 
diff --git a/pkg/analysis_server/lib/src/context_manager.dart b/pkg/analysis_server/lib/src/context_manager.dart
index 10acd68..4a1e4c1 100644
--- a/pkg/analysis_server/lib/src/context_manager.dart
+++ b/pkg/analysis_server/lib/src/context_manager.dart
@@ -4,7 +4,6 @@
 
 import 'dart:async';
 import 'dart:collection';
-import 'dart:core';
 
 import 'package:analysis_server/src/services/correction/fix/data_driven/transform_set_parser.dart';
 import 'package:analyzer/error/listener.dart';
diff --git a/pkg/analysis_server/lib/src/domain_analysis.dart b/pkg/analysis_server/lib/src/domain_analysis.dart
index df5d9f6..1208bd9 100644
--- a/pkg/analysis_server/lib/src/domain_analysis.dart
+++ b/pkg/analysis_server/lib/src/domain_analysis.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/computer/computer_hover.dart';
diff --git a/pkg/analysis_server/lib/src/domain_analytics.dart b/pkg/analysis_server/lib/src/domain_analytics.dart
index e3fe532..66df103 100644
--- a/pkg/analysis_server/lib/src/domain_analytics.dart
+++ b/pkg/analysis_server/lib/src/domain_analytics.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/protocol/protocol.dart';
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
diff --git a/pkg/analysis_server/lib/src/domain_diagnostic.dart b/pkg/analysis_server/lib/src/domain_diagnostic.dart
index f11ad7f..59056f2 100644
--- a/pkg/analysis_server/lib/src/domain_diagnostic.dart
+++ b/pkg/analysis_server/lib/src/domain_diagnostic.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/protocol/protocol.dart';
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
diff --git a/pkg/analysis_server/lib/src/domain_execution.dart b/pkg/analysis_server/lib/src/domain_execution.dart
index 9a79bf1..f047af1 100644
--- a/pkg/analysis_server/lib/src/domain_execution.dart
+++ b/pkg/analysis_server/lib/src/domain_execution.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:collection';
-import 'dart:core';
 
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/src/analysis_server.dart';
diff --git a/pkg/analysis_server/lib/src/domain_kythe.dart b/pkg/analysis_server/lib/src/domain_kythe.dart
index 990588e..ec59917 100644
--- a/pkg/analysis_server/lib/src/domain_kythe.dart
+++ b/pkg/analysis_server/lib/src/domain_kythe.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/protocol/protocol.dart';
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/uri_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/uri_contributor.dart
index 14fac8f..227c538 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/uri_contributor.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/uri_contributor.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
 import 'package:analyzer/dart/ast/ast.dart';
diff --git a/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart b/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart
index 06c0c17..7be1db5c1 100644
--- a/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart
+++ b/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/services/correction/change_workspace.dart';
diff --git a/pkg/analysis_server/lib/src/services/correction/executable_parameters.dart b/pkg/analysis_server/lib/src/services/correction/executable_parameters.dart
index 7200eec..824b3eb 100644
--- a/pkg/analysis_server/lib/src/services/correction/executable_parameters.dart
+++ b/pkg/analysis_server/lib/src/services/correction/executable_parameters.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.
 
-import 'dart:core';
-
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/analysis/session_helper.dart';
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index d0e51d0..c99707b 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
 import 'package:analysis_server/src/services/correction/base_processor.dart';
diff --git a/pkg/analysis_server/lib/src/services/refactoring/move_file.dart b/pkg/analysis_server/lib/src/services/refactoring/move_file.dart
index f768861..6e97072 100644
--- a/pkg/analysis_server/lib/src/services/refactoring/move_file.dart
+++ b/pkg/analysis_server/lib/src/services/refactoring/move_file.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.
 
-import 'dart:core';
-
 import 'package:analysis_server/src/protocol_server.dart' hide Element;
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
diff --git a/pkg/analyzer/lib/file_system/overlay_file_system.dart b/pkg/analyzer/lib/file_system/overlay_file_system.dart
index 563954b..8d7ce33 100644
--- a/pkg/analyzer/lib/file_system/overlay_file_system.dart
+++ b/pkg/analyzer/lib/file_system/overlay_file_system.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:convert';
-import 'dart:core';
 import 'dart:typed_data';
 
 import 'package:analyzer/file_system/file_system.dart';
diff --git a/pkg/analyzer/lib/src/analysis_options/analysis_options_provider.dart b/pkg/analyzer/lib/src/analysis_options/analysis_options_provider.dart
index c96c08e..efb2263 100644
--- a/pkg/analyzer/lib/src/analysis_options/analysis_options_provider.dart
+++ b/pkg/analyzer/lib/src/analysis_options/analysis_options_provider.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/source/source_resource.dart';
diff --git a/pkg/analyzer/lib/src/context/builder.dart b/pkg/analyzer/lib/src/context/builder.dart
index ec0aaa7..00a24f1 100644
--- a/pkg/analyzer/lib/src/context/builder.dart
+++ b/pkg/analyzer/lib/src/context/builder.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:collection';
-import 'dart:core';
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:yaml/yaml.dart';
diff --git a/pkg/analyzer/lib/src/source/package_map_resolver.dart b/pkg/analyzer/lib/src/source/package_map_resolver.dart
index 86bf901..0feee31 100644
--- a/pkg/analyzer/lib/src/source/package_map_resolver.dart
+++ b/pkg/analyzer/lib/src/source/package_map_resolver.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/util/asserts.dart' as asserts;
diff --git a/pkg/analyzer/lib/src/workspace/bazel.dart b/pkg/analyzer/lib/src/workspace/bazel.dart
index db72308..19f6fce 100644
--- a/pkg/analyzer/lib/src/workspace/bazel.dart
+++ b/pkg/analyzer/lib/src/workspace/bazel.dart
@@ -4,7 +4,6 @@
 
 import 'dart:async';
 import 'dart:collection';
-import 'dart:core';
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/dart/analysis/experiments.dart';
diff --git a/pkg/analyzer/lib/src/workspace/bazel_watcher.dart b/pkg/analyzer/lib/src/workspace/bazel_watcher.dart
index 05ce4a6..d1e3f26 100644
--- a/pkg/analyzer/lib/src/workspace/bazel_watcher.dart
+++ b/pkg/analyzer/lib/src/workspace/bazel_watcher.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
-import 'dart:core';
 import 'dart:io' as io;
 import 'dart:isolate';
 import 'dart:math';
diff --git a/pkg/analyzer/lib/src/workspace/gn.dart b/pkg/analyzer/lib/src/workspace/gn.dart
index 1746ddd..bb958e2 100644
--- a/pkg/analyzer/lib/src/workspace/gn.dart
+++ b/pkg/analyzer/lib/src/workspace/gn.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/context/packages.dart';
 import 'package:analyzer/src/generated/sdk.dart';
diff --git a/pkg/analyzer/lib/src/workspace/package_build.dart b/pkg/analyzer/lib/src/workspace/package_build.dart
index 7e0c179..7adef41 100644
--- a/pkg/analyzer/lib/src/workspace/package_build.dart
+++ b/pkg/analyzer/lib/src/workspace/package_build.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/context/packages.dart';
 import 'package:analyzer/src/generated/sdk.dart';
diff --git a/pkg/analyzer/test/embedder_tests.dart b/pkg/analyzer/test/embedder_tests.dart
index 8ad116d..3a84d69 100644
--- a/pkg/analyzer/test/embedder_tests.dart
+++ b/pkg/analyzer/test/embedder_tests.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 
diff --git a/pkg/analyzer/test/error/error_test.dart b/pkg/analyzer/test/error/error_test.dart
index b0a7875..afad0dc 100644
--- a/pkg/analyzer/test/error/error_test.dart
+++ b/pkg/analyzer/test/error/error_test.dart
@@ -2,7 +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.
 
-import 'dart:core';
 import 'dart:io';
 
 import 'package:analyzer/dart/analysis/features.dart';
diff --git a/pkg/analyzer/test/resource_utils.dart b/pkg/analyzer/test/resource_utils.dart
index d51194e..680004d 100644
--- a/pkg/analyzer/test/resource_utils.dart
+++ b/pkg/analyzer/test/resource_utils.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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
diff --git a/pkg/analyzer/test/source/analysis_options_provider_test.dart b/pkg/analyzer/test/source/analysis_options_provider_test.dart
index 787f65c..1c9d463 100644
--- a/pkg/analyzer/test/source/analysis_options_provider_test.dart
+++ b/pkg/analyzer/test/source/analysis_options_provider_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.
 
-import 'dart:core';
-
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/analysis_options/analysis_options_provider.dart';
diff --git a/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart b/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
index b62c1c1..586f202 100644
--- a/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
+++ b/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
@@ -4,7 +4,6 @@
 
 // @dart = 2.9
 
-import 'dart:core';
 import 'package:dev_compiler/src/kernel/module_symbols.dart';
 import 'package:test/test.dart';
 
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
index 654c67a..4a559f2 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.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.md file.
 
-import 'dart:core';
-
 import 'package:_fe_analyzer_shared/src/flow_analysis/flow_analysis.dart';
 
 import 'package:_fe_analyzer_shared/src/testing/id.dart';
diff --git a/pkg/kernel/lib/ast.dart b/pkg/kernel/lib/ast.dart
index 2ebf049..c8da9c7 100644
--- a/pkg/kernel/lib/ast.dart
+++ b/pkg/kernel/lib/ast.dart
@@ -64,7 +64,6 @@
 ///
 library kernel.ast;
 
-import 'dart:core';
 import 'dart:collection' show ListBase;
 import 'dart:convert' show utf8;
 
diff --git a/pkg/test_runner/lib/src/browser_controller.dart b/pkg/test_runner/lib/src/browser_controller.dart
index 02289f4..2920dc1 100644
--- a/pkg/test_runner/lib/src/browser_controller.dart
+++ b/pkg/test_runner/lib/src/browser_controller.dart
@@ -4,7 +4,6 @@
 
 import 'dart:async';
 import 'dart:convert';
-import 'dart:core';
 import 'dart:io';
 import 'dart:math';
 
diff --git a/pkg/vm/lib/transformations/specializer/map_factory_specializer.dart b/pkg/vm/lib/transformations/specializer/map_factory_specializer.dart
index 55f9d52..e25ce12 100644
--- a/pkg/vm/lib/transformations/specializer/map_factory_specializer.dart
+++ b/pkg/vm/lib/transformations/specializer/map_factory_specializer.dart
@@ -4,7 +4,6 @@
 
 import 'package:kernel/ast.dart';
 import 'package:kernel/core_types.dart';
-import 'dart:core';
 
 import 'package:vm/transformations/specializer/factory_specializer.dart';
 
diff --git a/tests/language_2/vm/div_mod_test.dart b/tests/language_2/vm/div_mod_test.dart
index 0d75505..0ce3c28 100755
--- a/tests/language_2/vm/div_mod_test.dart
+++ b/tests/language_2/vm/div_mod_test.dart
@@ -11,8 +11,6 @@
 
 import "package:expect/expect.dart";
 
-import 'dart:core';
-
 int kMin = 0x8000000000000000;
 int kMax = 0x7fffffffffffffff;
 
diff --git a/tools/VERSION b/tools/VERSION
index 6fdeec8..470204da 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 15
 PATCH 0
-PRERELEASE 83
+PRERELEASE 84
 PRERELEASE_PATCH 0
\ No newline at end of file