27735 Roll Skia from a4953515af8e to 097a9a475951 (1 revision) (cla: yes, waiting for tree to go green)

27737 TimePoint::Now uses DartTimestampProvider (cla: yes)

27739 Prepare for updated avoid_classes_with_only_static_members lint (cla: yes, waiting for tree to go green, platform-web, needs tests)

27741 [web] Code cleanup (cla: yes, platform-web)

27742 Add a run_tests flag that captures core dumps from engine unit tests and runs a GDB script (cla: yes, waiting for tree to go green)