Reland "[BlinkGenPropertyTrees] Fix ElementIsAnimatingChanged logic"

This relands the commit b0eab4a3e36612417196e6766d7a770f675169c4 from

The only change is to mark virtual/threaded/animations/skew-notsequential-compositor.html
as flaky; it has been decided that it is worth landing the CL anyway
and investigating the flakiness afterwards.,

Bug: 912574, 921105
Change-Id: I93dfc5db4056e3567f99254f28b1072a66c4f532
Reviewed-by: Stephen McGruer <>
Reviewed-by: Philip Rogers <>
Commit-Queue: Stephen McGruer <>
Cr-Commit-Position: refs/heads/master@{#622123}
14 files changed