Roll engine 104f0572802c..3860a43379fa (5 commits) (#23271)

https://github.com/flutter/engine/compare/104f0572802c...3860a43379fa

git log 104f0572802c..3860a43379fa --no-merges --oneline
3860a4337 Re-revert wrong line_heights implementation (flutter/engine#6598)
09dcc3d5e Gate locale.getScript() behind version check for android  API < 21 (flutter/engine#6592)
c17624479 Provide an estimate of EngineLayer memory usage to the Dart GC (flutter/engine#6589)
2511dec76 Roll src/third_party/skia a64e4eeaa357..b4ae49937d83 (14 commits) (flutter/engine#6590)
0887dd58f Roll buildroot to 4ee38927dc45c46f2a1c74b1e3700b3cf953e747 (flutter/engine#6586)

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bin/internal/engine.version

-104f0572802c9304b9e0f655b3d44cac5a4f4ca0
+3860a43379fa3a7474427a671c794fa29e555c10