diff --git a/.dart_tool/package_config.json b/.dart_tool/package_config.json
index a988d58..d468fbd 100644
--- a/.dart_tool/package_config.json
+++ b/.dart_tool/package_config.json
@@ -11,7 +11,7 @@
     "constraint, update this by running tools/generate_package_config.dart."
   ],
   "configVersion": 2,
-  "generated": "2021-11-10T09:58:01.876670",
+  "generated": "2021-11-15T17:34:02.415038",
   "generator": "tools/generate_package_config.dart",
   "packages": [
     {
@@ -659,7 +659,7 @@
       "name": "stream_channel",
       "rootUri": "../third_party/pkg/stream_channel",
       "packageUri": "lib/",
-      "languageVersion": "2.10"
+      "languageVersion": "2.14"
     },
     {
       "name": "string_scanner",
diff --git a/DEPS b/DEPS
index a4e2e0f..e29b322 100644
--- a/DEPS
+++ b/DEPS
@@ -155,7 +155,7 @@
   "source_span_rev": "1be3c44045a06dff840d2ed3a13e6082d7a03a23",
   "sse_rev": "9084339389eb441d0c0518cddac211a097e78657",
   "stack_trace_rev": "6788afc61875079b71b3d1c3e65aeaa6a25cbc2f",
-  "stream_channel_rev": "d7251e61253ec389ee6e045ee1042311bced8f1d",
+  "stream_channel_rev": "3fa3e40c75c210d617b8b943b9b8f580e9866a89",
   "string_scanner_rev": "1b63e6e5db5933d7be0a45da6e1129fe00262734",
   "sync_http_rev": "b59c134f2e34d12acac110d4f17f83e5a7db4330",
   "test_descriptor_rev": "ead23c1e7df079ac0f6457a35f7a71432892e527",
diff --git a/pkg/analyzer/lib/src/dart/sdk/sdk.dart b/pkg/analyzer/lib/src/dart/sdk/sdk.dart
index 35fb194..b23e091 100644
--- a/pkg/analyzer/lib/src/dart/sdk/sdk.dart
+++ b/pkg/analyzer/lib/src/dart/sdk/sdk.dart
@@ -46,17 +46,6 @@
   @override
   List<String> get uris => libraryMap.uris;
 
-  /// Add the extensions from one or more sdk extension files to this sdk. The
-  /// [extensions] should be a table mapping the names of extensions to the
-  /// paths where those extensions can be found.
-  void addExtensions(Map<String, String> extensions) {
-    extensions.forEach((String uri, String path) {
-      SdkLibraryImpl library = SdkLibraryImpl(uri);
-      library.path = path;
-      libraryMap.setLibrary(uri, library);
-    });
-  }
-
   /// Return info for debugging https://github.com/dart-lang/sdk/issues/35226.
   Map<String, Object> debugInfo() {
     return <String, Object>{
diff --git a/pkg/analyzer/test/src/dart/sdk/sdk_test.dart b/pkg/analyzer/test/src/dart/sdk/sdk_test.dart
index 6af1989..40d24dd 100644
--- a/pkg/analyzer/test/src/dart/sdk/sdk_test.dart
+++ b/pkg/analyzer/test/src/dart/sdk/sdk_test.dart
@@ -122,17 +122,6 @@
 
 @reflectiveTest
 class FolderBasedDartSdkTest with ResourceProviderMixin {
-  void test_addExtensions() {
-    FolderBasedDartSdk sdk = _createDartSdk();
-    String uri = 'dart:my.internal';
-    sdk.addExtensions({uri: '/Users/user/dart/my.dart'});
-    expect(sdk.mapDartUri(uri), isNotNull);
-    // The `shortName` property must include the `dart:` prefix.
-    expect(sdk.sdkLibraries, contains(predicate((SdkLibrary library) {
-      return library.shortName == uri;
-    })));
-  }
-
   void test_creation() {
     FolderBasedDartSdk sdk = _createDartSdk();
     expect(sdk, isNotNull);
diff --git a/tools/VERSION b/tools/VERSION
index 0fd0143..fb4f871 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 16
 PATCH 0
-PRERELEASE 15
+PRERELEASE 16
 PRERELEASE_PATCH 0
\ No newline at end of file