Fix build failure (#84597)
Fix build failure (#84597)

Fixes an incorrect cast that caused a build failure.

Landing on red to fix the build.
Hixie/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,Hixie/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,tvolkert/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,flutter/flutter,flutter/flutter,tvolkert/flutter