remove forever-deprecated and hidden f64 methods

[cyrgani]

The methods f64::is_positive and f64::is_negative were deprecated since 1.0 and marked as #[doc(hidden)] in favor of f64::is_sign_positive and f64::is_sign_negative. They also only exist on f64, not on f32. But for some unknown reason, they have been marked as stable.

This PR proposes to remove both methods as they were never a part of the documented API, assuming that a crater run finds no significant breakage.

[rustbot]

r? @joboet

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They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

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Why was this reviewer chosen?

The reviewer was selected based on:

• Owners of files modified in this PR: @scottmcm, libs
• @scottmcm, libs expanded to 8 candidates
• Random selection from Mark-Simulacrum, joboet, scottmcm

[jieyouxu]

@bors try @craterbot check

[rust-bors]

☀️ Try build successful (CI)
Build commit: 63132bd (63132bd615c9bf75e93af8405d00064212331708, parent: 3645249d79dfb136b5d8de3ce153d19d6698d92d)

[jieyouxu]

@craterbot check

[craterbot]

👌 Experiment pr-153975 created and queued.
🤖 Automatically detected try build 63132bd
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[Amanieu]

Assuming crater results come back clean...

@rfcbot merge libs-api

[rust-rfcbot]

Team member @Amanieu has proposed to merge this. The next step is review by the rest of the tagged team members:

• @Amanieu
• @BurntSushi
• @dtolnay
• @joshtriplett
• @the8472

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

[scottmcm]

r=me assuming FCP completes and crater is clean 🙂

r? scottmcm

[craterbot]

🚧 Experiment pr-153975 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🎉 Experiment pr-153975 is completed!
📊 5 regressed and 5 fixed (854500 total)
📊 6128 spurious results on the retry-regressed-list.txt, consider a retry¹ if this is a significant amount.
📰 Open the summary report.

⚠️ If you notice any spurious failure please add them to the denylist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

Footnotes

1. re-run the experiment with crates=https://crater-reports.s3.amazonaws.com/pr-153975/retry-regressed-list.txt ↩

[WaffleLapkin]

Looked at the crater report, it is indeed clean :)