Missing results in rustdoc search

[ollie27]

Results that differ in only the parent type are missing in the search results. For example searching is_nan misses f64::is_nan: https://doc.rust-lang.org/nightly/std/?search=is_nan. It also says there are 4 results but only shows 3.

This is a stable to beta regression caused by #49757. cc. @GuillaumeGomez