Don't NFC normalize filenames in form data

LayoutTests/http/tests/xmlhttprequest/filename-encoding-expected.txt

Index: LayoutTests/http/tests/xmlhttprequest/filename-encoding-expected.txt
diff --git a/LayoutTests/http/tests/xmlhttprequest/filename-encoding-expected.txt b/LayoutTests/http/tests/xmlhttprequest/filename-encoding-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..46f967431e46bac3111d4546936c5dff515f9afb
--- /dev/null
+++ b/LayoutTests/http/tests/xmlhttprequest/filename-encoding-expected.txt
@@ -0,0 +1,14 @@
+Verify that attachment filenames are not normalized
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS file.name is request.filename
+PASS response.field is request.field
+PASS response.filename is request.filename
+PASS response.type is request.type
+PASS response.content is request.content
+PASS successfullyParsed is true
+
+TEST COMPLETE
+