…-type-names-fix, r=oli-obk,wesleywiser

Handle non-integer const generic parameters in debuginfo type names.

This PR fixes an ICE introduced by rust-lang#85269 which started emitting const generic arguments for debuginfo names but did not cover the case where such an argument could not be evaluated to a flat string of bits.

The fix implemented in this PR is very basic: If `try_eval_bits()` fails for the constant in question, we fall back to generating a stable hash of the constant and emit that instead. This way we get a (virtually) unique name and side step the problem of generating a string representation of a potentially complex value.

The downside is that the generated name will be rather opaque. E.g. the regression test adds a function `const_generic_fn_non_int<()>` which is then rendered as `const_generic_fn_non_int<{CONST#fe3cfa0214ac55c7}>`. I think it's an open question how to deal with this more gracefully.

I'd be interested in ideas on how to do this better.

r? ```@wesleywiser```

cc ```@dpaoliello``` (do you see any problems with this approach?)
cc ```@Mark-Simulacrum``` & ```@nagisa``` (who I've seen comment on debuginfo issues recently -- anyone else?)

Fixes rust-lang#86893

…, r=notriddle

Search result colors

Part of  rust-lang#87072 (fixes the first and fourth regressions and add tests to prevent it from happening again).

cc ```@Nemo157```

r? ```@camelid```

Make BTreeSet::split_off name elements like other set methods do

r? ```@Mark-Simulacrum```

…trochenkov

Unignore some pretty printing tests

Closes rust-lang#37201
r? ```@petrochenkov```

…richton

Upgrade `cc` crate to 1.0.69

This pulls another fix for rust-lang#83043, i.e., rust-lang/cc-rs#605.
r? `@alexcrichton`

… r=Manisheart,notriddle

Add GUI test for "go to first" feature

It adds a test for rust-lang#85876 to ensure the feature is working as expected and prevent potential regression.

cc ``@jeanlucthumm``

r? ``@Manishearth``