[Windows] Refactor virtual-env image generation provisioners (#1288)

* refactor virtual-env image generation provisioners

images/win/scripts/Installers/Install-VS.ps1

@@ -0,0 +1,52 @@
+################################################################################
+##  File:  Install-VS.ps1
+##  Desc:  Install Visual Studio
+################################################################################
+
+$ErrorActionPreference = "Stop"
+
+$toolset = Get-ToolsetContent
+$requiredComponents = $toolset.visualStudio.workloads | ForEach-Object { "--add $_" }
+$workLoads = @(
+	"--allWorkloads --includeRecommended"
+	$requiredComponents
+	"--remove Component.CPython3.x64"
+)
+$workLoadsArgument = [String]::Join(" ", $workLoads)
+
+$releaseInPath = $toolset.visualStudio.edition
+$subVersion = $toolset.visualStudio.subversion
+$bootstrapperUrl = "https://aka.ms/vs/${subVersion}/release/vs_${releaseInPath}.exe"
+
+# Install VS
+Install-VisualStudio -BootstrapperUrl $bootstrapperUrl -WorkLoads $workLoadsArgument
+
+# Find the version of VS installed for this instance
+# Only supports a single instance
+$vsProgramData = Get-Item -Path "C:\ProgramData\Microsoft\VisualStudio\Packages\_Instances"
+$instanceFolders = Get-ChildItem -Path $vsProgramData.FullName
+
+if ($instanceFolders -is [array])
+{
+    Write-Host "More than one instance installed"
+    exit 1
+}
+
+$vsInstallRoot = Get-VisualStudioPath
+
+# Initialize Visual Studio Experimental Instance
+& "$vsInstallRoot\Common7\IDE\devenv.exe" /RootSuffix Exp /ResetSettings General.vssettings /Command File.Exit
+
+# Updating content of MachineState.json file to disable autoupdate of VSIX extensions
+$newContent = '{"Extensions":[{"Key":"1e906ff5-9da8-4091-a299-5c253c55fdc9","Value":{"ShouldAutoUpdate":false}},{"Key":"Microsoft.VisualStudio.Web.AzureFunctions","Value":{"ShouldAutoUpdate":false}}],"ShouldAutoUpdate":false,"ShouldCheckForUpdates":false}'
+Set-Content -Path "$vsInstallRoot\Common7\IDE\Extensions\MachineState.json" -Value $newContent
+
+if (Test-IsWin19) {
+	# Install Windows 10 SDK version 10.0.14393.795
+	$sdkUrl = "https://go.microsoft.com/fwlink/p/?LinkId=838916"
+	$sdkFileName = "sdksetup14393.exe"
+	$argumentList = ("/q", "/norestart", "/ceip off", "/features OptionId.WindowsSoftwareDevelopmentKit")
+	Install-Binary -Url $sdkUrl -Name $sdkFileName -ArgumentList $argumentList
+}
+
+Invoke-PesterTests -TestFile "VisualStudio"