22026 Roll Dart SDK from 874709e52a99 to a3d902d8598e (1 revision) (cla: yes, waiting for tree to go green)

22033 Add a golden scenario test for fallback font rendering on iOS take 2 (cla: yes, waiting for tree to go green)

22041 Ensure root isolate create callback is invoked before the isolate is in the running phase. (cla: yes, waiting for tree to go green)

22055 Roll Fuchsia Mac SDK from pZ9FgVZTK… to WLxBkBnZa… (cla: yes, waiting for tree to go green)

22057 Roll Fuchsia Linux SDK from lPMs_KwnU… to gqS_DIjN4… (cla: yes, waiting for tree to go green)