Bug 1269712 - <track kind=invalid> should behave like metadata, not subtitles; r=bz

This follows a spec change <https://github.com/whatwg/html/issues/293>,
which AFAIK no other browser has implemented, so it has some regression
potential.

The web-platform tests changed are out-of-date and match the old spec,
so I'm changing them here to match the new spec.

dom/html/HTMLTrackElement.cpp

@@ -69,8 +69,9 @@ static MOZ_CONSTEXPR nsAttrValue::EnumTable kKindTable[] = {
   { 0 }
 };
 
-// The default value for kKindTable is "subtitles"
-static MOZ_CONSTEXPR const char* kKindTableDefaultString = kKindTable[0].tag;
+// Invalid values are treated as "metadata" in ParseAttribute, but if no value
+// at all is specified, it's treated as "subtitles" in GetKind
+static MOZ_CONSTEXPR const nsAttrValue::EnumTable* kKindTableInvalidValueDefault = &kKindTable[4];
 
 /** HTMLTrackElement */
 HTMLTrackElement::HTMLTrackElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
@@ -96,7 +97,7 @@ NS_INTERFACE_MAP_END_INHERITING(nsGenericHTMLElement)
 void
 HTMLTrackElement::GetKind(DOMString& aKind) const
 {
-  GetEnumAttr(nsGkAtoms::kind, kKindTableDefaultString, aKind);
+  GetEnumAttr(nsGkAtoms::kind, kKindTable[0].tag, aKind);
 }
 
 void
@@ -170,7 +171,8 @@ HTMLTrackElement::ParseAttribute(int32_t aNamespaceID,
 {
   if (aNamespaceID == kNameSpaceID_None && aAttribute == nsGkAtoms::kind) {
     // Case-insensitive lookup, with the first element as the default.
-    return aResult.ParseEnumValue(aValue, kKindTable, false, kKindTable);
+    return aResult.ParseEnumValue(aValue, kKindTable, false,
+                                  kKindTableInvalidValueDefault);
   }
 
   // Otherwise call the generic implementation.

dom/html/test/test_track.html

@@ -24,7 +24,7 @@ reflectLimitedEnumerated({
                 "metadata"],
   invalidValues: ["foo", "bar", "\u0000", "null", "", "subtitle", "caption",
                   "description", "chapter", "meta"],
-  defaultValue: "subtitles"
+  defaultValue: { missing: "subtitles", invalid: "metadata" },
 });
 
 // Default attribute

testing/web-platform/tests/html/semantics/embedded-content/media-elements/interfaces/HTMLElement/HTMLTrackElement/kind.html

@@ -13,7 +13,7 @@ test(function(){
 test(function(){
     var track = document.createElement('track');
     track.setAttribute('kind', 'invalid');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
     assert_equals(track.getAttribute('kind'), 'invalid');
 }, document.title + ' invalid value in content attribute');
 
@@ -27,14 +27,14 @@ test(function(){
 test(function(){
     var track = document.createElement('track');
     track.setAttribute('kind', 'CAPT\u0130ONS');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
     assert_equals(track.getAttribute('kind'), 'CAPT\u0130ONS');
 }, document.title + ' content attribute with uppercase turkish I (with dot)');
 
 test(function(){
     var track = document.createElement('track');
     track.setAttribute('kind', 'capt\u0131ons');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
     assert_equals(track.getAttribute('kind'), 'capt\u0131ons');
 }, document.title + ' content attribute with lowercase turkish i (dotless)');
 
@@ -76,7 +76,7 @@ test(function(){
 test(function(){
     var track = document.createElement('track');
     track.setAttribute('kind', 'captions\u0000');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
     assert_equals(track.getAttribute('kind'), 'captions\u0000');
 }, document.title + ' content attribute "captions\\u0000"');
 
@@ -126,21 +126,21 @@ test(function(){
     var track = document.createElement('track');
     track.kind = 'CAPT\u0130ONS';
     assert_equals(track.getAttribute('kind'), 'CAPT\u0130ONS');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
 }, document.title + ' setting IDL attribute with uppercase turkish I (with dot)');
 
 test(function(){
     var track = document.createElement('track');
     track.kind = 'capt\u0131ons';
     assert_equals(track.getAttribute('kind'), 'capt\u0131ons');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
 }, document.title + ' setting IDL attribute with lowercase turkish I (dotless)');
 
 test(function(){
     var track = document.createElement('track');
     track.kind = 'captions\u0000';
     assert_equals(track.getAttribute('kind'), 'captions\u0000');
-    assert_equals(track.kind, 'subtitles');
+    assert_equals(track.kind, 'metadata');
 }, document.title + ' setting IDL attribute with \\u0000');
 
 </script>

testing/web-platform/tests/html/semantics/embedded-content/media-elements/interfaces/TextTrack/kind.html

@@ -26,6 +26,6 @@ test(function(){
 test(function(){
     var track = document.createElement('track');
     track.kind = 'captions\u0000';
-    assert_equals(track.track.kind, 'subtitles');
+    assert_equals(track.track.kind, 'metadata');
 }, document.title+', \\u0000');
 </script>