- Change Group.prototype.size to .length
- Use window.requestAnimationFrame when streaming-loading files to show
  the loading animation
- Limit width of the timeline-track legend and add 'title' attribute
  to show the full text when cropped
- Add duration for selected timeline events in timeline-track legend
- Better error message when the local symbol server is not available

Bug: v8:10644
Change-Id: Icdf2042341c9355ecb55e2fd8e6a4fa0feb5968f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3003151Reviewed-by: Patrick Thier <pthier@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75549}