Revert Dart SDK to f59531cc2973 (#30729)

* Revert "Roll Dart SDK from 5f2c54513b7d to 8a8fb0972646 (1 revision) (#30725)"

This reverts commit 496e05526ea26a9273616984bd97f458afca1b2b.

* Revert "Roll Dart SDK from f59531cc2973 to 5f2c54513b7d (13 revisions) (#30716)"

This reverts commit 38a007d125b0e1970e09759fbb20fb23449994bc.
diff --git a/DEPS b/DEPS
index 257584e..18aa35b 100644
--- a/DEPS
+++ b/DEPS
@@ -39,7 +39,7 @@
   # 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': '8a8fb0972646c81ff2f33675bfa9a38454b7bdfa',
+  'dart_revision': 'f59531cc2973c893927b6d6b2cc7204919d50cc4',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -226,7 +226,7 @@
    Var('dart_git') + '/html.git@00cd3c22dac0e68e6ed9e7e4945101aedb1b3109',
 
   'src/third_party/dart/third_party/pkg/http':
-   Var('dart_git') + '/http.git@1e42ffa181b263f7790f276a5465832bff7ce615',
+   Var('dart_git') + '/http.git@f35d1e1467092f6a5edb2abf7071c4a99e8c737a',
 
   'src/third_party/dart/third_party/pkg/http_multi_server':
    Var('dart_git') + '/http_multi_server.git@de1b312164c24a1690b46c6e97bd47eff40c4649',
@@ -298,7 +298,7 @@
    Var('dart_git') + '/source_maps.git@6499ee3adac8d469e2953e2e8ba4bdb4c2fbef90',
 
   'src/third_party/dart/third_party/pkg/source_span':
-   Var('dart_git') + '/source_span.git@dc189b455d823e2919667f6c5dcb41ab7483bce0',
+   Var('dart_git') + '/source_span.git@1be3c44045a06dff840d2ed3a13e6082d7a03a23',
 
   'src/third_party/dart/third_party/pkg/sse':
    Var('dart_git') + '/sse.git@9084339389eb441d0c0518cddac211a097e78657',
diff --git a/ci/licenses_golden/licenses_third_party b/ci/licenses_golden/licenses_third_party
index dcc2756..7bb163d 100644
--- a/ci/licenses_golden/licenses_third_party
+++ b/ci/licenses_golden/licenses_third_party
@@ -1,4 +1,4 @@
-Signature: 8df0b617b98d1aec1368689a09b39b61
+Signature: 49a681051f210ef77fe2c686e6a67701
 
 UNUSED LICENSES:
 
@@ -9772,8 +9772,6 @@
 FILE: ../../../third_party/dart/benchmarks/FfiAsTypedList/dart2/FfiAsTypedList.dart
 FILE: ../../../third_party/dart/benchmarks/IsolateFibonacci/dart/IsolateFibonacci.dart
 FILE: ../../../third_party/dart/benchmarks/IsolateFibonacci/dart2/IsolateFibonacci.dart
-FILE: ../../../third_party/dart/benchmarks/MapCopy/dart/MapCopy.dart
-FILE: ../../../third_party/dart/benchmarks/MapCopy/dart2/MapCopy.dart
 FILE: ../../../third_party/dart/benchmarks/MapLookup/dart/MapLookup.dart
 FILE: ../../../third_party/dart/benchmarks/MapLookup/dart/maps.dart
 FILE: ../../../third_party/dart/benchmarks/MapLookup/dart2/MapLookup.dart