rustdoc: fix and re-enable help widget on mobile

[lolbinarycat]

fixes #77899

[rustbot]

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[rustbot]

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez, @jsha

[GuillaumeGomez]

It'll be fixed by #129545. I don't think it's a good idea to make changes (for the help menu on mobile) before this one is merged.

[lolbinarycat]

ah, i wasn't aware of that PR, i assumed that no progress was being made on the issue since it was 4 years old.

[GuillaumeGomez]

Ah we didn't link to it, good point! Gonna update the PR so it mentions the issue.

[rust-log-analyzer]

The job x86_64-gnu-tools failed! Check out the build log: (web) (plain)

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.......... (130/131)
F          (131/131)


/checkout/tests/rustdoc-gui/scrape-examples-layout.goml scrape-examples-layout... FAILED
[ERROR] `tests/rustdoc-gui/scrape-examples-layout.goml` line 85: The following errors happened: [different Y values: 288 (or 288) != 284]: for command `assert-position: (".scraped-example", {"y": 284})`
[ERROR] `tests/rustdoc-gui/scrape-examples-layout.goml` line 86: The following errors happened: [different Y values: 316 (or 316) != 312]: for command `assert-position: (".scraped-example .prev", {"y": 284 + |offset_y| + |title_height|})`
Error: ()
Build completed unsuccessfully in 0:03:12
  local time: Mon Sep 16 21:26:29 UTC 2024
  network time: Mon, 16 Sep 2024 21:26:29 GMT