The TL(custom-v8) task started to often hit the task's run limit of 1h this week.

There is one task which still ran in 12 minutes like the older ones, newer ones are close to an hour or hit the limit.

This successful but long running task has two "hangs":

[task 2020-05-22T11:37:48.655Z] # Get v8 source code and dependencies
[task 2020-05-22T11:37:48.655Z] fetch v8
[task 2020-05-22T11:37:48.655Z] + fetch v8
[task 2020-05-22T11:38:14.026Z] Warning: Running gclient on Python 3. 
[task 2020-05-22T11:38:14.026Z] If you encounter any issues, please file a bug on crbug.com under the Infra>SDK component.
[task 2020-05-22T11:38:14.026Z] WARNING: Your metrics.cfg file was invalid or nonexistent. A new one will be created.
[task 2020-05-22T11:38:15.773Z] Warning: Running gclient on Python 3. 
[task 2020-05-22T11:38:15.773Z] If you encounter any issues, please file a bug on crbug.com under the Infra>SDK component.
[task 2020-05-22T12:02:29.859Z] 
[task 2020-05-22T12:02:29.859Z] ________ running 'git -c core.deltaBaseCacheLimit=2g clone --no-checkout --progress https://chromium.googlesource.com/v8/v8.git /builds/worker/workspace/build/src/_gclient_v8_t2n6y0lc' in '/builds/worker/workspace/build/src'

[task 2020-05-22T12:03:05.722Z] Resolving deltas: 100% (644078/644078)   
[task 2020-05-22T12:03:05.722Z] Resolving deltas: 100% (644078/644078), done.
[task 2020-05-22T12:27:46.782Z] [0:49:29] Still working on:
[task 2020-05-22T12:27:46.782Z] [0:49:29]   v8
[task 2020-05-22T12:28:17.953Z] ________ running 'vpython v8/third_party/depot_tools/update_depot_tools_toggle.py --disable' in '/builds/worker/workspace/build/src'

Please redirect the needinfo to Greg if appropriate.

This patch attempts to fix the long-running customv8 toolchain tasks by adding a --force to the fetch v8 call. This additional option prevents fetch from checking for existing .gclient files (which should never exist) to help with the long delay we are seeing in this call.

This patch should address the issue.

Try 1: https://treeherder.mozilla.org/#/jobs?repo=try&revision=2e9a12ecf675994ea6d20c8bcc2f6caaa6dca526
Try 2: https://treeherder.mozilla.org/#/jobs?repo=try&revision=f0937f71bd2cff5d970678743a08af1e15df7f4e

https://hg.mozilla.org/mozilla-central/rev/7291cf51007b