Improve caption button behavior for video player.

third_party/WebKit/LayoutTests/media/media-controls.js

Index: third_party/WebKit/LayoutTests/media/media-controls.js
diff --git a/third_party/WebKit/LayoutTests/media/media-controls.js b/third_party/WebKit/LayoutTests/media/media-controls.js
index 673e92aac340729f0748358ae9e20de04396ab20..367b0c3711beb07a63aec5e09509ba6878508f98 100644
--- a/third_party/WebKit/LayoutTests/media/media-controls.js
+++ b/third_party/WebKit/LayoutTests/media/media-controls.js
@@ -133,7 +133,8 @@ function clickAtCoordinates(x, y)
 function textTrackListItemAtIndex(video, index)
 {
     var textTrackListElementID = "-internal-media-controls-text-track-list";
-    var textTrackListElement = mediaControlsElement(internals.shadowRoot(video).firstChild, textTrackListElementID);
+    var textTrackListElement = mediaControlsElement(
+            internals.shadowRoot(video).firstChild, textTrackListElementID);
     if (!textTrackListElement)
         throw "Failed to find text track list element";
 
@@ -145,10 +146,16 @@ function textTrackListItemAtIndex(video, index)
     }
 }
 
-function clickTextTrackAtIndex(video, index)
+function clickCaptionButton(video)
 {
-    var captionsButtonCoordinates = mediaControlsButtonCoordinates(video, "toggle-closed-captions-button");
+    var captionsButtonCoordinates =
+            mediaControlsButtonCoordinates(video, "toggle-closed-captions-button");
     clickAtCoordinates(captionsButtonCoordinates[0], captionsButtonCoordinates[1]);
+}
+
+function clickTextTrackAtIndex(video, index)
+{
+    clickCaptionButton(video);
     var trackListItemElement = textTrackListItemAtIndex(video, index);
     var trackListItemCoordinates = elementCoordinates(trackListItemElement);
     clickAtCoordinates(trackListItemCoordinates[0], trackListItemCoordinates[1]);
@@ -159,6 +166,18 @@ function turnClosedCaptionsOff(video)
     clickTextTrackAtIndex(video, -1);
 }
 
+function checkCaptionsVisible(video, captions)
+{
+    for (var i = 0; i < captions.length; i++) {
+      assert_equals(textTrackCueElementByIndex(video, i).innerText, captions[i]);
+    }
+}
+
+function checkCaptionsHidden(video)
+{
+    assert_equals(textTrackDisplayElement(video), null);
+}
+
 function runAfterHideMediaControlsTimerFired(func, mediaElement)
 {
     if (mediaElement.paused)