Roll Flutter Engine from 5df7af34a718 to 2eef9b43cfb4 (4 revisions) (#136774)

https://github.com/flutter/engine/compare/5df7af34a718...2eef9b43cfb4

2023-10-17 chris@bracken.jp Move imgui from buildroot to flutter third_party (flutter/engine#47031)
2023-10-17 jonahwilliams@google.com [Impeller] Rework Vulkan GPUTracker to decorate existing cmd buffers. (flutter/engine#46963)
2023-10-17 chris@bracken.jp [fml][embedder] Improve thread-check logging (flutter/engine#47020)
2023-10-17 skia-flutter-autoroll@skia.org Roll Dart SDK from 99ce477503f8 to da48c75b73b1 (1 revision) (flutter/engine#47027)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC jimgraham@google.com,rmistry@google.com,zra@google.com on the revert to ensure that a human
is aware of the problem.

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https://issues.skia.org/issues/new?component=1389291&template=1850622

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bin/internal/engine.version

-5df7af34a7183b00a1f9e1e271740fb4d9fe67e3
+2eef9b43cfb40dd9cad907606f18735b85197cef