23179 Roll Dart SDK from b59de86059f3 to 2a78a2978983 (1 revision) (cla: yes, waiting for tree to go green)

23180 Roll Skia from dfc880bd9ba0 to 5d3227096daa (8 revisions) (cla: yes, waiting for tree to go green)

23181 Roll Dart SDK from 2a78a2978983 to c91b639b4cb3 (1 revision) (cla: yes, waiting for tree to go green)

23182 Roll Skia from 5d3227096daa to 7bfdb1044916 (1 revision) (cla: yes, waiting for tree to go green)

23187 Re-merge Switch web-render option default to auto. Add documentation (cla: yes)