[Installer] Gracefully terminate PowerToys process before updating do… (#20430)

* [Installer] Gracefully terminate PowerToys process before updating dotnet

installer/PowerToysSetup/PowerToys.wxs

@@ -72,6 +72,16 @@
       <util:RegistrySearch Variable="DetectedVCRedistVersion" Root="HKLM" Key="Software\Microsoft\VisualStudio\14.0\VC\Runtimes\$(var.PowerToysPlatform)" Value="Minor" Result="value" Format="raw" />
 
         <Chain>
+            <ExePackage
+                Name="terminate_powertoys.cmd"
+                Cache="no"
+                Compressed="yes"
+                Id="TerminatePowerToys"
+                SourceFile="terminate_powertoys.cmd"
+                Permanent="yes"
+                PerMachine="yes"
+                Vital="no">
+            </ExePackage>
             <ExePackage
                 Name="windowsdesktop-runtime-6.0.8-win-$(var.PowerToysPlatform).exe"
                 Compressed="no"

installer/PowerToysSetup/terminate_powertoys.cmd

@@ -0,0 +1,12 @@
+@echo off
+setlocal ENABLEDELAYEDEXPANSION
+
+@REM We loop here until taskkill cannot find a PowerToys process. We can't use /F flag, because it
+@REM doesn't give application an opportunity to cleanup. Thus we send WM_CLOSE which is being caught
+@REM by multiple windows running a msg loop in PowerToys.exe process, which we close one by one.
+for /l %%x in (1, 1, 100) do (
+    taskkill /IM PowerToys.exe 1>NUL 2>NUL
+    if !ERRORLEVEL! NEQ 0 goto quit
+)
+
+:quit