- Categorize more instance types
- Fix GC selection dropdown labels
- Show GC times in seconds
- Collapse file reader after loading

Bug: v8:7266
Change-Id: If967ebdb887105e808cfc8fb3bc92f9da5c91fd2
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/945908Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51690}