Revert "Roll engine 77c5812d48b8..84dc383b6428 (16 commits) (#51072)" (#51212)
Revert "Roll engine 77c5812d48b8..84dc383b6428 (16 commits) (#51072)" (#51212)

This reverts commit 0b5667ac12b073295403780bd3a38fd88db7a273.
cbracken/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,cbracken/flutter,cbracken/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,cbracken/flutter,flutter/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,cbracken/flutter,cbracken/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,tvolkert/flutter,Hixie/flutter,Hixie/flutter,cbracken/flutter,Hixie/flutter,flutter/flutter,cbracken/flutter,tvolkert/flutter,Hixie/flutter