Use structured logging on Fuchsia (#49918)

This change migrates off of the old fuchsia logging apis to use the
structured logging apis. The initial FIDL connection is made during
global initialization (before main()) and the initial minimum log level
is queried from the system. Later on, once the main loop is initialized,
we setup an async task to listen for additional log interest changes
from the system. The advantage of doing this on the main loop is that we
avoid spawning an additional background thread in the process (the
legacy logging apis use the background thread approach).

One added benefit of this change is it reduces the size of the
dart/flutter runner far packages by about 250kb in release mode, because
libsyslog.so and libbackend_fuchsia_globals.so are no longer needed.

flutter/flutter#141924

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14 files changed
tree: 47db6a2ccfc8637f9947b9485733a208b200fdc9
  1. .github/
  2. assets/
  3. benchmarking/
  4. build/
  5. ci/
  6. common/
  7. display_list/
  8. docs/
  9. examples/
  10. flow/
  11. flutter_frontend_server/
  12. flutter_vma/
  13. fml/
  14. impeller/
  15. lib/
  16. runtime/
  17. shell/
  18. skia/
  19. sky/
  20. testing/
  21. third_party/
  22. tools/
  23. vulkan/
  24. wasm/
  25. web_sdk/
  26. .ci.yaml
  27. .clang-format
  28. .clang-tidy
  29. .gitattributes
  30. .gitignore
  31. .pylintrc
  32. .style.yapf
  33. analysis_options.yaml
  34. AUTHORS
  35. BUILD.gn
  36. CODEOWNERS
  37. CONTRIBUTING.md
  38. DEPS
  39. Doxyfile
  40. LICENSE
  41. README.md
README.md

Flutter Engine

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