19104 Roll Dart SDK from f36151e2d2a2 to 0c2c331d64f3 (13 revisions) (cla: yes, waiting for tree to go green)

19106 Roll buildroot to 2415cd5095c186fe5054552bbb26aaa2b8877ac8 (cla: yes, waiting for tree to go green)

19107 Roll Skia from de175abede4d to 72f403c343dc (127 revisions) (cla: yes, waiting for tree to go green)

19108 [shell] Adds a shell test for timezone fetches (cla: yes)

19109 [fuchsia] Adds –targets arg for build_fuchsia_artifacts.py (cla: yes)