AK: Stub out AK::demangle on Windows

Author: https://github.com/stasoid
Commit: 9884cd0628
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2914
Reviewed-by: https://github.com/AtkinsSJ ✅

AK/Demangle.h

@@ -8,10 +8,14 @@
 
 #include <AK/ByteString.h>
 #include <AK/StringView.h>
-#include <cxxabi.h>
+
+#ifndef AK_OS_WINDOWS
+#    include <cxxabi.h>
+#endif
 
 namespace AK {
 
+#ifndef AK_OS_WINDOWS
 inline ByteString demangle(StringView name)
 {
     int status = 0;
@@ -21,6 +25,13 @@ inline ByteString demangle(StringView name)
         free(demangled_name);
     return string;
 }
+#else
+inline ByteString demangle(StringView name)
+{
+    // FIXME: Implement AK::demangle on Windows
+    return name;
+}
+#endif
 
 }