Fixes https://github.com/flutter/flutter/issues/55219

* Speedup color to css string 25%

This change converts all Float64List matrices to Float32List at the dart:ui interface boundary. Internally, it only uses Float32List. Float32List requires less memory and is orders of magnitude faster to allocate, and it has sufficient precision as Flutter mobile engine and Skia use 32-bit floats anyway.

This change speeds up frame preroll by 50% on the bench_card_infinite_scroll benchmark.

For more details on Float64Array allocation in JS (which backs Float64List in Dart) see the following:

https://bugs.chromium.org/p/v8/issues/detail?id=9199
https://bugs.chromium.org/p/v8/issues/detail?id=2022

* add scenebuilder submetrics
* Disable Profiler by default

* Pass amber-files directory to tests.

Bug:
  https://github.com/flutter/flutter/issues/50249
  https://github.com/flutter/flutter/issues/55165

* Redirect tar stdout to dev/null and fix param name.

* Keep scenic tests disabled.

The C++ text input model used by Windows and Linux currently uses UTF-32. The intention was to facilitate handling of arrow keys, backspace/delete, etc., however since part of what is synchronized with the engine is cursor+selection offsets, and those offsets are defined in terms of UTF-16 code units, this causes very bad interactions with the framework-side model.

This converts to using UTF-16, rather than UTF-32, so that the offsets align with the framework. It also adds surrogate pair handling to the operations that adjust indexes, to avoid breaking surrogate pairs. (Arbitrary grapheme cluster handling is out of scope for this PR; while definitely desirable in the long term, surrogate pair handling is much more critical since improper handling yields invalid UTF-16, which breaks the text field).

This partially fixes https://github.com/flutter/flutter/issues/55014. A framework-side fix is also necessary (since currently both the engine and the framework attempt to handle arrow keys, which is another out-of-scope-for-this-PR issue), but even without the framework fix this dramatically improves the cursor behavior on Windows when there are surrogate pairs somewhere in the string since at least the two sides agree on what indexes mean.

Includes minor plumbing changes to the text input plumbing on Windows so that we're not pointlessly converting from UTF-16 to UTF-32 and then back to UTF-16.

Builds flags have been switched, so the old versions aren't needed any
longer.

* Change backdrop filter element location based on ancestor clip. Add test.
* update test
* Addressed review comments. updated goldens
* Check ancestor on retain
* addressed review comments