Devtools Animations: Collapse animations in the timeline

Currently, each animation is shown on a separate row. This change collapses
animations targetting the same element where possible. This has the advantage
of saving vertical UI space and logically combining animations targeting the
same element.

This change also removes the display of sequence numbers as an animation name.

BUG=447083

Review URL: https://codereview.chromium.org/942733003

git-svn-id: svn://svn.chromium.org/blink/trunk@190874 bbb929c8-8fbe-4397-9dbb-9b2b20218538
3 files changed
tree: 6076bf3d6006ab4b554d46aabdb643b79a49a287
  1. third_party/