Manual roll Flutter from b1a28bc065b0 to 6cc976ec26d3 (4 revisions) (#10116)

Manual roll requested by [email protected]

flutter/flutter@b1a28bc...6cc976e

2025-09-25 [email protected] [Impeller] Optimize scale translate rectangle transforms (flutter/flutter#171841)
2025-09-25 [email protected] [time_picker] refactor: Distinguish widgets for dial mode only (flutter/flutter#173188)
2025-09-25 [email protected] Reapply "Update the AccessibilityPlugin::Announce method to account f… (flutter/flutter#174365)
2025-09-25 [email protected] Put Linux firebase_release_smoke_test on bringup (flutter/flutter#176043)

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Author: engine-flutter-autoroll

.ci/flutter_master.version

@@ -1 +1 @@
-b1a28bc065b0acc50bc2284be87a9a708bd7aa85
+6cc976ec26d3a69cc3f53331f25e46e0b8189342