Roll engine 87edd94e9cc7..c48774cfe09b (3 commits) (#29079)

https://github.com/flutter/engine/compare/87edd94e9cc7...c48774cfe09b

git log 87edd94e9cc751a0de72c0828d41793b9f740062..c48774cfe09b7f286defb9e457a74c7e7028e11c --no-merges --oneline
c48774cfe Roll src/third_party/dart 571ea80e11..2fb6cd9f5f (122 commits) (flutter/engine#8086)
3c8ef04e9 Allow embedders to post tasks onto the render thread. (flutter/engine#8089)
1d10e0eb6 Guard against NewAPI failures (flutter/engine#8048)

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bin/internal/engine.version

-87edd94e9cc751a0de72c0828d41793b9f740062
+c48774cfe09b7f286defb9e457a74c7e7028e11c