Roll Dart SDK from b177ece3a265 to 489ccc317a9a (2 revisions) (flutter/engine#37227)

DEPS

@@ -48,7 +48,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/main/DEPS.
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': 'b177ece3a26561dacfdc4b527ef74ee504ba8907',
+  'dart_revision': '489ccc317a9a8f5b3bbd13a6aa6fa311e41ac3b8',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -57,7 +57,7 @@ vars = {
   'dart_browser_launcher_rev': '981ca8847dd2b0fe022f9e742045cfb8f214d35f',
   'dart_clock_rev': '97026d1657566bb0c9f5a33642712ec350e45084',
   'dart_collection_rev': 'efd709fc1760a595f8575f4137a1847de1b49d76',
-  'dart_devtools_rev': 'b21cd59f1f6bb60cacd59ba39e376d2a50d82f74',
+  'dart_devtools_rev': '23444af89d716818f099974df3e4fffac87fd886',
   'dart_protobuf_rev': 'ba29983968de5b54196c6c2a5cff1afbdda24ae2',
   'dart_pub_rev': '6506cc01b1bd17aff782037817d86a88a1c312e8',
   'dart_root_certificates_rev': '692f6d6488af68e0121317a9c2c9eb393eb0ee50',
@@ -180,7 +180,7 @@ deps = {
   # WARNING: Unused Dart dependencies in the list below till "WARNING:" marker are removed automatically - see create_updated_flutter_deps.py.
 
   'src/third_party/dart/third_party/devtools':
-   {'packages': [{'version': 'git_revision:b21cd59f1f6bb60cacd59ba39e376d2a50d82f74', 'package': 'dart/third_party/flutter/devtools'}], 'dep_type': 'cipd'},
+   {'packages': [{'version': 'git_revision:23444af89d716818f099974df3e4fffac87fd886', 'package': 'dart/third_party/flutter/devtools'}], 'dep_type': 'cipd'},
 
   'src/third_party/dart/third_party/pkg/args':
    Var('dart_git') + '/args.git@aaf671c1462108d62b1dba0e4a74f98ed233d939',
@@ -255,7 +255,7 @@ deps = {
    Var('dart_git') + '/logging.git@f322480fb9d9e83e677c08db6d09067059f7ff74',
 
   'src/third_party/dart/third_party/pkg/markdown':
-   Var('dart_git') + '/markdown.git@49eefd211e7840bac7e11257cd966435ae3cb07f',
+   Var('dart_git') + '/markdown.git@f3873403f5b1a0319f78632a8fbc2b22315a7b83',
 
   'src/third_party/dart/third_party/pkg/matcher':
    Var('dart_git') + '/matcher.git@6a9b83bbd73e50df2058b3e8e4aa301df49569c6',