Bug 298928 – Script 'update-angle' assumess target Webkit commit is always main

• Component: New Bugs
• Status: RESOLVED FIXED

[Diego Pino]

Recently we had to bisect an ANGLE update interval:

```
5f80c14d9917 2025-05-26 [e-mail]  Update ANGLE to 2025-05-19 (dcbcee8ab32af9ddc7ae1e91c42d995e5281602c) https://bugs.webkit.org/show_bug.cgi?id=293282 rdar://151678098
cf222c5b83fc 2025-04-28 [e-mail]  Update ANGLE to 2025-04-25 (34d30914048ac98a6f50f84aa630cc285b75bc79) https://bugs.webkit.org/show_bug.cgi?id=292054 rdar://problem/150026170
```

The goal was to rollback to WebKit commit cf222c5b83fc (last good known commit) and use the script 'update-angle' to bisect the ANGLE interval: 34d30914048ac98a6f50f84aa630cc285b75bc79..dcbcee8ab32af9ddc7ae1e91c42d995e5281602c.

However, the 'update-angle' script as it is right now is not useful because when it creates the 'just-angle' branch it has 'main' hardcoded as WebKit commit. What that implies is that, even if I am in cf222c5b83fc and run "Tools/Scripts/update-angle b4d39a07b3" (b4d39a07b3 is one commit before dcbcee8ab), the script will set PREVIOUS_ANGLE_COMMIT_HASH to the last ANGLE commit updated in WebKit main and LAST_ROLL_COMMIT_HASH to the last WebKit commit that touched the ANGLE.plist file.

What we would like in this scenario is that 'update-angle' doesn't see ANGLE changes beyond a certain WebKit commit (in this case, one commit before 5f80c14d9917).

[Diego Pino]

Pull request: https://github.com/WebKit/WebKit/pull/50794

[EWS]

Committed 300020@main (08137aa17cea): <https://commits.webkit.org/300020@main>

Reviewed commits have been landed. Closing PR #50794 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/160678757>