24860 Roll Dart SDK from b191fb71063c to 64a5583ffbc9 (2 revisions) (cla: yes, waiting for tree to go green)

24862 Roll Fuchsia Mac SDK from Rw36pWO5J… to C8RDwF3IB… (cla: yes, waiting for tree to go green)

24863 Roll Fuchsia Linux SDK from hnDJ6SZhJ… to yDVPrfGq5… (cla: yes, waiting for tree to go green)

24865 Send -1 for empty composition range (cla: yes, waiting for tree to go green)

24873 Adds setText to web engine (cla: yes, waiting for tree to go green)