ci: download WiX on Windows

Avoid requiring Windows CI hosts to have WiX installed.

.gitlab/ci/wix.ps1

+$erroractionpreference = "stop"
+
+$release = "wix3112rtm"
+$sha256sum = "2C1888D5D1DBA377FC7FA14444CF556963747FF9A0A289A3599CF09DA03B9E2E"
+$filename = "wix311-binaries"
+$tarball = "$filename.zip"
+
+$outdir = $pwd.Path
+$outdir = "$outdir\.gitlab"
+$ProgressPreference = 'SilentlyContinue'
+Invoke-WebRequest -Uri "https://github.com/wixtoolset/wix3/releases/download/$release/$tarball" -OutFile "$outdir\$tarball"
+$hash = Get-FileHash "$outdir\$tarball" -Algorithm SHA256
+if ($hash.Hash -ne $sha256sum) {
+    exit 1
+}
+
+Add-Type -AssemblyName System.IO.Compression.FileSystem
+[System.IO.Compression.ZipFile]::ExtractToDirectory("$outdir\$tarball", "$outdir\wix\bin")

.gitlab/os-windows.yml

@@ -72,9 +72,12 @@
 ## Windows-specific scripts
 
 .before_script_windows: &before_script_windows
+    - Invoke-Expression -Command .gitlab/ci/wix.ps1
     - Invoke-Expression -Command .gitlab/ci/cmake.ps1
     - Invoke-Expression -Command .gitlab/ci/ninja.ps1
     - $pwdpath = $pwd.Path
+    - Set-Item -Force -Path "env:WIX" -Value "$pwdpath\.gitlab\wix"
+    - (& "$env:WIX\bin\light.exe" -help) | Select -First 1
     - Set-Item -Force -Path "env:PATH" -Value "$pwdpath\.gitlab;$pwdpath\.gitlab\cmake\bin;$env:PATH"
     - cmake --version
     - ninja --version