[fuchsia] Fix failing SDK roll. (#30675)

diff --git a/shell/platform/fuchsia/flutter/software_surface.cc b/shell/platform/fuchsia/flutter/software_surface.cc
index f5ef369..be3e474 100644
--- a/shell/platform/fuchsia/flutter/software_surface.cc
+++ b/shell/platform/fuchsia/flutter/software_surface.cc
@@ -8,6 +8,7 @@
 #include <lib/ui/scenic/cpp/commands.h>
 #include <zircon/status.h>
 #include <zircon/types.h>
+#include <zx/cpp/fidl.h>
 
 #include <cmath>