26459 Roll Dart SDK from e6f56536dd12 to efccf1e46351 (8 revisions) (cla: yes, waiting for tree to go green)

26460 Better logging pthread_setspecific (cla: yes, waiting for tree to go green)

26461 Roll Skia from ace17c2f4689 to 35981296a8f4 (3 revisions) (cla: yes, waiting for tree to go green)

26462 Make litetest throw on test failure instead of exit() (cla: yes)

26463 Add debug symbols (symbol-index) to serve.sh for Fuchsia. (cla: yes, waiting for tree to go green, platform-fuchsia)