Reland "Support 'xcode parallelization' flag on the test blocks level."

This reverts commit c79a7556da9e8e45df3dc0a160d8dd304a2b25cf.

Reason for revert: discussed offline; should be fine on branches due to how run.py parses args_json.

Original change's description:
> Revert "Support 'xcode parallelization' flag on the test blocks level."
> 
> This reverts commit 0f143592b6e3c6db8e13280055065f7ea6b38f1f.
> 
> Reason for revert: xcode parallelization flag should only be present for M73+.
> 
> Original change's description:
> > Support 'xcode parallelization' flag on the test blocks level.
> > 
> > Bug:920300
> > Change-Id: I6a926e12788bff54811b3c034106516e31224a88
> > Recipe-Nontrivial-Roll: build_limited_scripts_slave
> > Reviewed-on: https://chromium-review.googlesource.com/c/1404137
> > Commit-Queue: Maksym Onufriienko <monufriienko@chromium.org>
> > Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>
> 
> TBR=justincohen@chromium.org,sergeyberezin@chromium.org,lindsayw@chromium.org,monufriienko@chromium.org
> 
> Change-Id: Id6d0cce488714bda96df7b2aba662c97993f5780
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 920300
> Reviewed-on: https://chromium-review.googlesource.com/c/1407213
> Reviewed-by: John Budorick <jbudorick@chromium.org>
> Commit-Queue: John Budorick <jbudorick@chromium.org>

TBR=justincohen@chromium.org,sergeyberezin@chromium.org,lindsayw@chromium.org,jbudorick@chromium.org,monufriienko@chromium.org

Change-Id: I3f27ea8a3567613442f08d1fb296e22b6e13e6e2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 920300
Reviewed-on: https://chromium-review.googlesource.com/c/1407218
Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>
40 files changed
tree: 1239a764b568af49ccf4cae2d1584390c13c5576
  1. .gitattributes
  2. .gitignore
  3. .vpython
  4. DEPS
  5. LICENSE
  6. OWNERS
  7. PRESUBMIT.py
  8. README.md
  9. WATCHLISTS
  10. codereview.settings
  11. environment.cfg.py
  12. infra/
  13. masters/
  14. scripts/
  15. site_config/
  16. slave/
  17. tests/
  18. third_party/
README.md

build

Hi build contributor! If you do any change in scripts/master/ or touching any master's html/ directories, you must restart master.chromium.fyi first and ensure that it still works before restarting other masters.

Recipes

If you're here to make a change to ‘recipes’ (the code located in scripts/slave/recipes*), please take a look at the README for more information pertaining to recipes.