no-bug: A few quality-of-life tweaks (build tooling)

[iskunk]

Hello, I am using some of the Zen build tools in an alternate setting, a framework that "converts" a Debian source package of Firefox into the equivalent Zen one. To that end, having some additional flexibility in the invocation of the tooling is helpful.

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package.json: Use the $CARGO environment variable if set, and pass arguments to ffprefs using the new convention (see below)

(E.g. on Ubuntu, there is generally not a cargo executable in PATH, but there may be a cargo-1.91. This is normally specified via the CARGO variable, similar to CC and CXX)

update_service_dumps.py: Allow specifying DUMPS_FOLDER and ENGINE_DUMPS_FOLDER on the command line

ffprefs/src/main.rs: Allow specifying the prefs and engine dirs on the command line instead of hard-coding their locations relative to a common root dir

[mr-cheffy]

Thanks!

[mr-cheffy]

Is this being used correctly? As the DIR might be different?

[iskunk]

Hm, I missed that relative-to-$CWD dir. It's effectively a third (if optional) input.

I've pushed an update to package.json that will run ffprefs in the top-level directory, instead of cd'ing down into tools/ffprefs/.

[Copilot]

Pull request overview

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[iskunk]

Thanks! I put in a companion PR for Surfer, along similar lines.

[mr-cheffy]

fails to run npm run import on windows. #13605

[iskunk]

Hm, I wasn't aware this needed to run on Windows. The ${CARGO:-cargo} bit is likely at fault.

I see there are some solutions to running OS-specific scripts in a package.json file, so I'll review those and put together a reland.