[Windows] Include packaging only when requested

Author: bnbarham

utils/build-windows-toolchain.bat

@@ -19,7 +19,7 @@ set TEMP=%~dp0..\..\tmp
 mkdir %TEMP% 2>&1 1>nul
 echo set PYTHON_HOME=%PYTHON_HOME%> %TEMP%\call-build.cmd
 echo set SKIP_TESTS=%SKIP_TESTS%>> %TEMP%\call-build.cmd
-echo set SKIP_PACKAGING=%SKIP_PACKAGING%>> %TEMP%\call-build.cmd
+echo set INCLUDE_PACKAGING=%INCLUDE_PACKAGING%>> %TEMP%\call-build.cmd
 echo set SKIP_UPDATE_CHECKOUT=%SKIP_UPDATE_CHECKOUT%>> %TEMP%\call-build.cmd
 echo set REPO_SCHEME=%REPO_SCHEME%>> %TEMP%\call-build.cmd
 echo set WINDOWS_SDKS=%WINDOWS_SDKS%>> %TEMP%\call-build.cmd
@@ -65,9 +65,9 @@ set TestArg=-Test lld,lldb,swift,dispatch,foundation,xctest,swift-format,sourcek
 for %%I in (%SKIP_TESTS%) do (call set TestArg=%%TestArg:%%I,=%%)
 if "%TestArg:~-1%"=="," (set TestArg=%TestArg:~0,-1%) else (set TestArg= )
 
-:: Build the -SkipPackaging argument, if any
-set SkipPackagingArg=-SkipPackaging
-if not "%SKIP_PACKAGING%"=="1" set "SkipPackagingArg= "
+:: Build the packaging arguments (skipped for normal PRs and an added stage for toolchain PRs)
+set "PackagingArg=-SkipPackaging"
+if not "%INCLUDE_PACKAGING%"=="" set "PackagingArg=-Stage %PackageRoot%"
 
 :: Build the -WindowsSDKArchitectures argument, if any, otherwise build all the SDKs.
 set "WindowsSDKArchitecturesArg= "
@@ -85,10 +85,9 @@ powershell.exe -ExecutionPolicy RemoteSigned -File %~dp0build.ps1 ^
   -SourceCache %SourceRoot% ^
   -BinaryCache %BuildRoot% ^
   -ImageRoot %BuildRoot% ^
-  %SkipPackagingArg% ^
+  %PackagingArg% ^
   %WindowsSDKArchitecturesArg% ^
   %TestArg% ^
-  -SkipPackaging ^
   -IncludeSBoM ^
   -Summary || (exit /b 1)