Imported Upstream version 4.3.2.467

Former-commit-id: 9c2cb47f45fa221e661ab616387c9cda183f283d

external/referencesource/System.Xml/InternalApis/NDP_Common/inc/Win8Helpers.cs

@@ -16,6 +16,11 @@ namespace Microsoft.Win32 {
     [System.Security.SuppressUnmanagedCodeSecurity]
     internal static class UnsafeNativeMethods
     {
+#if !FEATURE_CORECLR
+        // On CoreCLR this is not the way to determine if a process is a tailored application (which means APPX).
+        // On CoreCLR AppX is determined by a flag past to the host which is exposed by AppDomain.IsAppXProcess in mscorlib.
+        // The reason for this if-def is to ensure nobody takes a dependency on this on CoreCLR.
+        
         internal const String KERNEL32 = "kernel32.dll";
 
         // WinError.h codes:
@@ -77,6 +82,7 @@ namespace Microsoft.Win32 {
 
         [System.Security.SecuritySafeCritical]
         internal static Lazy<bool> IsPackagedProcess = new Lazy<bool>(() => _IsPackagedProcess());
+#endif //!FEATURE_CORECLR
     }
 }