[libcxx] [llvm] [libc++] Use GitHub-provided runners for the windows CI (PR #79326)

[Nikolas Klauser via llvm-commits]

https://github.com/philnik777 updated https://github.com/llvm/llvm-project/pull/79326

>From 8864a679b4b08eb4bb0be90b1f7409d42965fd17 Mon Sep 17 00:00:00 2001
From: Nikolas Klauser <nikolasklauser at berlin.de>
Date: Wed, 24 Jan 2024 17:42:53 +0100
Subject: [PATCH] [libc++] Use GitHub-provided runners for the windows CI

---
 .github/workflows/libcxx-build-and-test.yaml | 16 ++++++++++++++++
 libcxx/trigger                               |  0
 2 files changed, 16 insertions(+)
 create mode 100644 libcxx/trigger

diff --git a/.github/workflows/libcxx-build-and-test.yaml b/.github/workflows/libcxx-build-and-test.yaml
index 5727b956dc6dd23..d5658fa5ffacb49 100644
--- a/.github/workflows/libcxx-build-and-test.yaml
+++ b/.github/workflows/libcxx-build-and-test.yaml
@@ -199,3 +199,19 @@ jobs:
             **/CMakeError.log
             **/CMakeOutput.log
             **/crash_diagnostics/*
+  windows:
+    runs-on: windows-2019
+    steps:
+      - uses: actions/checkout at v4
+      - name: Install dependencies
+        run: |
+          choco install -y ninja wget
+          wget https://github.com/mstorsjo/llvm-mingw/releases/download/20231128/llvm-mingw-20231128-ucrt-x86_64.zip -O llvm-mingw.zip
+          powershell Expand-Archive llvm-mingw.zip -DestinationPath .
+          del llvm-mingw.zip
+          ren llvm-mingw-20231128-ucrt-x86_64 llvm-mingw
+      - name: clang-cl (DLL)
+        run: |
+          "powershell -Command [System.Environment]::SetEnvironmentVariable('PATH', [System.Environment]::GetEnvironmentVariable('PATH', 'machine') + ';C:\Program Files\Git\usr\bin;C:\llvm-mingw\bin' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\CommonExt ensions\Microsoft\TeamFoundation\Team Explorer' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\CommonExtensions\Microsoft\CMake\Ninja' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\CommonExtensions\Microsoft\TeamFoundation\Team Explorer' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\CommonExtensions\Microsoft\TestWindow' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\IDE\VC\VCPackages' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\Tools\' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\Tools\devinit' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\bin\Roslyn' + ';C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Tools\MSVC\14.29.30133\bin\HostX64\x64' + ';C:\Program Files (x86)\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.8 Tools\x64\' + ';C:\Program Files (x86)\Windows Kits\10\bin\10.0.19041.0\x64' + ';C:\Program Files (x86)\Windows Kits\10\bin\x64' + ';C:\Windows\Microsoft.NET\Framework64\v4.0.30319', 'machine')"
+          cmd /k echo %path%
+          bash libcxx/utils/ci/run-buildbot clang-cl-dll
diff --git a/libcxx/trigger b/libcxx/trigger
new file mode 100644
index 000000000000000..e69de29bb2d1d64