Roll libc++ from 98409c6c0983 to bf30ab1b37bc (9 revisions)

https://chromium.googlesource.com/external/github.com/llvm/llvm-project/libcxx.git/+log/98409c6c0983..bf30ab1b37bc

2025-04-14 [email protected] [libc++] Removes the _LIBCPP_VERBOSE_ABORT_NOT_NOEXCEPT macro. (#135494)
2025-04-13 [email protected] [libc++] Replace __libcpp_popcount by __builtin_popcountg (#133937)
2025-04-13 [email protected] [libc++] Use __underlying_type directly in underyling_type_t (#135423)
2025-04-13 [email protected] [libc++][test][NFC] Remove unused inclusions of `<iostream>` (#134776)
2025-04-13 [email protected] [libc++][test] Test `nasty_string` in C++20 (#135338)
2025-04-13 [email protected] [libc++][NFC] Reuse `__bit_log2` for `sort` (#135303)
2025-04-12 [email protected] [libc++][NFC] Remove a few aliases in __tree (#134392)
2025-04-12 [email protected] [libc++][doc] Updates the release notes.
2025-04-12 [email protected] [NFC][libc++][test] Minor updates to generated header version test. (#134543)

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Tbr: [email protected],[email protected]
Change-Id: Ic05f23d80df4fa623bc7b9cb68668c3a63e45bf8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6454951
Bot-Commit: chromium-autoroll <[email protected]>
Commit-Queue: chromium-autoroll <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1446680}
NOKEYCHECK=True
GitOrigin-RevId: 8b11155ca6f8f71885e724b63b743228edf41eda

Author: chromium-autoroll

deps_revisions.gni

@@ -5,5 +5,5 @@
 declare_args() {
   # Used to cause full rebuilds on libc++ rolls. This should be kept in sync
   # with the libcxx_revision var in //DEPS.
-  libcxx_revision = "98409c6c0983bf04803fb6913fd25741d4eb6b0b"
+  libcxx_revision = "bf30ab1b37bc976f82a46fa7f15e30235c4a1a49"
 }