Bug 1276831 - part4 : modify web-platform-test. r=rillian

The idl-test-harness can't detect the multiple types in webidl [1], so it doesn't know about the type like "double or AutoKeyword".
The same problem also happen in VTTCue's line property, and we have already expected its fail.
Therefore, we should expect this fail before we fix the problem of idl-test-harness.

[1] http://searchfox.org/mozilla-central/source/dom/imptests/idlharness.js#375
MozReview-Commit-ID: 5XvOwdmqKDP

--HG--
extra : rebase_source : fd72ef43d1f24792a1b3e228da7a7dca9483b1da

testing/web-platform/meta/webvtt/interfaces.html.ini

@@ -18,6 +18,9 @@
   [VTTCue interface: new VTTCue(0, 1, "foo") must inherit property "line" with the proper type (3)]
     expected: FAIL
 
+  [VTTCue interface: new VTTCue(0, 1, "foo") must inherit property "position" with the proper type (5)]
+    expected: FAIL
+
   [VTTRegion interface: existence and properties of interface object]
     expected: FAIL
 

testing/web-platform/tests/webvtt/interfaces.html

@@ -19,7 +19,7 @@ interface VTTCue : TextTrackCue {
            attribute boolean snapToLines;
            attribute (double or AutoKeyword) line;
            attribute AlignSetting lineAlign;
-           attribute double position;
+           attribute (double or AutoKeyword) position;
            attribute AlignSetting positionAlign;
            attribute double size;
            attribute AlignSetting align;