In Windows 8 (and 8.1), runtime winmds may contain assembly refs pointing
to other runtime winmds (for example, types defined in Windows.UI.Xaml
point to Windows.UI).  However, when the EE sees these assembly refs it
must redirect them back to the compile time contract assembly (Windows),
because the Compilation used by the EE only references the contract Assembly,
not the various runtime Assemblies.  Previously, we only did this redirection
for Windows 10.  Non-EE cases should only see the contract assembly at
compile time, so this change will not affect them.