5 files changed, 78 insertions, 2 deletions
diff --git a/components/script/dom/webidls/HTMLMediaElement.webidl b/components/script/dom/webidls/HTMLMediaElement.webidl
index fa0459e0921..27e9d79c78d 100644
--- a/components/script/dom/webidls/HTMLMediaElement.webidl
+++ b/components/script/dom/webidls/HTMLMediaElement.webidl
@@ -61,6 +61,6 @@ interface HTMLMediaElement : HTMLElement {
   // tracks
   // readonly attribute AudioTrackList audioTracks;
   // readonly attribute VideoTrackList videoTracks;
-  // readonly attribute TextTrackList textTracks;
-  // TextTrack addTextTrack(TextTrackKind kind, optional DOMString label = "", optional DOMString language = "");
+  readonly attribute TextTrackList textTracks;
+  TextTrack addTextTrack(TextTrackKind kind, optional DOMString label = "", optional DOMString language = "");
 };
diff --git a/components/script/dom/webidls/TextTrack.webidl b/components/script/dom/webidls/TextTrack.webidl
new file mode 100644
index 00000000000..71fc0e84099
--- /dev/null
+++ b/components/script/dom/webidls/TextTrack.webidl
@@ -0,0 +1,30 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#texttrack
+
+enum TextTrackMode { "disabled",  "hidden",  "showing" };
+enum TextTrackKind { "subtitles",  "captions",  "descriptions",  "chapters",  "metadata" };
+
+[Exposed=Window]
+interface TextTrack : EventTarget {
+  readonly attribute TextTrackKind kind;
+  readonly attribute DOMString label;
+  readonly attribute DOMString language;
+
+  readonly attribute DOMString id;
+  // readonly attribute DOMString inBandMetadataTrackDispatchType;
+
+  attribute TextTrackMode mode;
+
+  readonly attribute TextTrackCueList? cues;
+  // readonly attribute TextTrackCueList? activeCues;
+
+  [Throws]
+  void addCue(TextTrackCue cue);
+  [Throws]
+  void removeCue(TextTrackCue cue);
+
+  attribute EventHandler oncuechange;
+};
diff --git a/components/script/dom/webidls/TextTrackCue.webidl b/components/script/dom/webidls/TextTrackCue.webidl
new file mode 100644
index 00000000000..20f1bf3f06d
--- /dev/null
+++ b/components/script/dom/webidls/TextTrackCue.webidl
@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#texttrackcue
+
+[Exposed=Window]
+interface TextTrackCue : EventTarget {
+  readonly attribute TextTrack? track;
+
+  attribute DOMString id;
+  attribute double startTime;
+  attribute double endTime;
+  attribute boolean pauseOnExit;
+
+  attribute EventHandler onenter;
+  attribute EventHandler onexit;
+};
diff --git a/components/script/dom/webidls/TextTrackCueList.webidl b/components/script/dom/webidls/TextTrackCueList.webidl
new file mode 100644
index 00000000000..357d8751bc2
--- /dev/null
+++ b/components/script/dom/webidls/TextTrackCueList.webidl
@@ -0,0 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#texttrackcuelist
+
+[Exposed=Window]
+interface TextTrackCueList {
+  readonly attribute unsigned long length;
+  getter TextTrackCue (unsigned long index);
+  TextTrackCue? getCueById(DOMString id);
+};
diff --git a/components/script/dom/webidls/TextTrackList.webidl b/components/script/dom/webidls/TextTrackList.webidl
new file mode 100644
index 00000000000..33e1bef0ff4
--- /dev/null
+++ b/components/script/dom/webidls/TextTrackList.webidl
@@ -0,0 +1,16 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#texttracklist
+
+[Exposed=Window]
+interface TextTrackList : EventTarget {
+  readonly attribute unsigned long length;
+  getter TextTrack (unsigned long index);
+  TextTrack? getTrackById(DOMString id);
+
+  attribute EventHandler onchange;
+  attribute EventHandler onaddtrack;
+  attribute EventHandler onremovetrack;
+};