Sync the DOMParser interface with spec

LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt

Index: LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt
diff --git a/LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt b/LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt
index 5e8f68029f11655571ed689a38f22d4f633c0675..0e1bae0ded9047715180850fd03fcb2dbf47affb 100644
--- a/LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt
+++ b/LayoutTests/fast/dom/domparser-parsefromstring-mimetype-support-expected.txt
@@ -23,19 +23,19 @@ Root element: svg
 PASS
 
 6. Should THROW exception for mime-type = "text/xsl"
-TypeError: Failed to execute 'parseFromString' on 'DOMParser': Unsupported mime-type specified.
+TypeError: Failed to execute 'parseFromString' on 'DOMParser': parameter 2 ('text/xsl') is not a valid enum value.
 PASS
 
 7. Should THROW exception for mime-type = "text/dummy+xml"
-TypeError: Failed to execute 'parseFromString' on 'DOMParser': Unsupported mime-type specified.
+TypeError: Failed to execute 'parseFromString' on 'DOMParser': parameter 2 ('text/dummy+xml') is not a valid enum value.
 PASS
 
 8. Should THROW exception for mime-type = "text/XML"
-TypeError: Failed to execute 'parseFromString' on 'DOMParser': Unsupported mime-type specified.
+TypeError: Failed to execute 'parseFromString' on 'DOMParser': parameter 2 ('text/XML') is not a valid enum value.
 PASS
 
 9. Should THROW exception for mime-type = "TEXT/html"
-TypeError: Failed to execute 'parseFromString' on 'DOMParser': Unsupported mime-type specified.
+TypeError: Failed to execute 'parseFromString' on 'DOMParser': parameter 2 ('TEXT/html') is not a valid enum value.
 PASS