WebM file fail to play

https://bugs.webkit.org/show_bug.cgi?id=242854
<rdar://97190939>

Reviewed by Eric Carlson.

If a track is disabled because it contains no data, the AV MediaPlayer will
flag the content as not playable even though it will play.

We can't properly test this change for the failing file as we rely on the
MediaFormatReader plugin to decode WebM which isn't available on the EWS bots.

* Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.h:
* Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.mm:
(WebCore::MediaPlayerPrivateAVFoundationObjC::allTracksArePlayable const):
(WebCore::MediaPlayerPrivateAVFoundationObjC::containsDisabledTracks const):
(WebCore::MediaPlayerPrivateAVFoundationObjC::assetStatus const):

Canonical link: https://commits.webkit.org/254219@main

Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.h

@@ -357,6 +357,7 @@ class MediaPlayerPrivateAVFoundationObjC final : public MediaPlayerPrivateAVFoun
     void checkNewVideoFrameMetadata();
 
     std::optional<bool> allTracksArePlayable() const;
+    bool containsDisabledTracks() const;
     bool trackIsPlayable(AVAssetTrack*) const;
 
     RetainPtr<AVURLAsset> m_avAsset;

Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.mm

@@ -1834,12 +1834,30 @@ static URL conformFragmentIdentifierForURL(const URL& url)
         return std::nullopt;
 
     for (AVAssetTrack *assetTrack : [m_avAsset tracks]) {
-        if (!trackIsPlayable(assetTrack))
+        if ([assetTrack isEnabled] && !trackIsPlayable(assetTrack))
             return false;
     }
     return true;
 }
 
+bool MediaPlayerPrivateAVFoundationObjC::containsDisabledTracks() const
+{
+    if (m_avPlayerItem) {
+        for (AVPlayerItemTrack *track in [m_avPlayerItem tracks]) {
+            if (![track isEnabled])
+                return true;
+        }
+        return false;
+    }
+
+    ASSERT(m_avAsset);
+    for (AVAssetTrack *assetTrack : [m_avAsset tracks]) {
+        if (![assetTrack isEnabled])
+            return true;
+    }
+    return false;
+}
+
 bool MediaPlayerPrivateAVFoundationObjC::trackIsPlayable(AVAssetTrack* track) const
 {
     if (player()->shouldCheckHardwareSupport() && !assetTrackMeetsHardwareDecodeRequirements(track, player()->mediaContentTypesRequiringHardwareSupport()))
@@ -1926,7 +1944,7 @@ static URL conformFragmentIdentifierForURL(const URL& url)
     }
 
     if (!m_cachedAssetIsPlayable)
-        m_cachedAssetIsPlayable = [[m_avAsset valueForKey:@"playable"] boolValue];
+        m_cachedAssetIsPlayable = [[m_avAsset valueForKey:@"playable"] boolValue] || containsDisabledTracks();
 
     if (*m_cachedAssetIsPlayable && *m_cachedTracksArePlayable)
         return MediaPlayerAVAssetStatusPlayable;