Fix powershell quotation issue, when CUSTOM_PARAMETERS contains spaces (#470)

dist/platforms/windows/build.ps1

@@ -109,6 +109,10 @@ Write-Output "#    Building project     #"
 Write-Output "###########################"
 Write-Output ""
 
+# If $Env:CUSTOM_PARAMETERS contains spaces and is passed directly on the command line to Unity, powershell will wrap it
+# in double quotes.  To avoid this, parse $Env:CUSTOM_PARAMETERS into an array, while respecting any quotations within the string.
+$_, $customParametersArray = Invoke-Expression('Write-Output -- "" ' + $Env:CUSTOM_PARAMETERS)
+
 & "C:\Program Files\Unity\Hub\Editor\$Env:UNITY_VERSION\Editor\Unity.exe" -quit -batchmode -nographics `
                                                                           -projectPath $Env:UNITY_PROJECT_PATH `
                                                                           -executeMethod $Env:BUILD_METHOD `
@@ -122,7 +126,7 @@ Write-Output ""
                                                                           -androidKeyaliasName $Env:ANDROID_KEYALIAS_NAME `
                                                                           -androidKeyaliasPass $Env:ANDROID_KEYALIAS_PASS `
                                                                           -androidTargetSdkVersion $Env:ANDROID_TARGET_SDK_VERSION `
-                                                                          $Env:CUSTOM_PARAMETERS `
+                                                                          $customParametersArray `
                                                                           -logfile | Out-Host
 
 # Catch exit code