Roll Flutter from c74a646b7bba to 47b5ed3948e8 (2 revisions) (#4914)

diff --git a/.ci/flutter_master.version b/.ci/flutter_master.version
index c09c5a5..438032a 100644
--- a/.ci/flutter_master.version
+++ b/.ci/flutter_master.version
@@ -1 +1 @@
-c74a646b7bba1641d0b2b29f6024dc867844e94c
+47b5ed3948e8ca3e79a120e220ad548d22f479bf