ad21c5adf Roll Dart SDK from bb6aa5a412d7 to eddf73d66119 (1 revision) (flutter/engine#37897) (#115986)

diff --git a/bin/internal/engine.version b/bin/internal/engine.version
index 22cad1e..7ed3e4e 100644
--- a/bin/internal/engine.version
+++ b/bin/internal/engine.version
@@ -1 +1 @@
-0930a7633348c825bf46d76063f8784187268aab
+ad21c5adfd651a1f85ef54a06df865f0e39fa86f