Bump pubspecs to unblock Dart SDK roller (#40297)

Bump pubspecs to unblock Dart SDK roller
diff --git a/lib/web_ui/pubspec.yaml b/lib/web_ui/pubspec.yaml
index f35dafa..3f688e4 100644
--- a/lib/web_ui/pubspec.yaml
+++ b/lib/web_ui/pubspec.yaml
@@ -3,7 +3,7 @@
 
 # Keep the SDK version range in sync with pubspecs under web_sdk
 environment:
-  sdk: ">=2.17.0-0 <3.0.0"
+  sdk: ">=2.19.0 <3.0.0"
 
 dependencies:
   js: 0.6.4
diff --git a/tools/path_ops/dart/pubspec.yaml b/tools/path_ops/dart/pubspec.yaml
index 1dca185..2db1908 100644
--- a/tools/path_ops/dart/pubspec.yaml
+++ b/tools/path_ops/dart/pubspec.yaml
@@ -8,7 +8,7 @@
 homepage: https://github.com/flutter/engine/tree/main/tools/path_ops
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.17.0 <3.0.0'
 
 dev_dependencies:
   litetest: any
diff --git a/web_sdk/pubspec.yaml b/web_sdk/pubspec.yaml
index 60dcc8d..c975813 100644
--- a/web_sdk/pubspec.yaml
+++ b/web_sdk/pubspec.yaml
@@ -2,7 +2,7 @@
 
 # Keep the SDK version range in sync with lib/web_ui/pubspec.yaml
 environment:
-  sdk: ">=2.12.0-0 <3.0.0"
+  sdk: ">=2.19.0 <3.0.0"
 
 dependencies:
   args: 2.3.1