REGRESSION(295500@main): [GStreamer] Assert when running http/tests/media/video-cross-site.html https://bugs.webkit.org/show_bug.cgi?id=294251

Reviewed by Xabier Rodriguez-Calvar.

Initialize Thunder key systems within the CDMFactory constructor, which is first called from
GStreamerCommon's initialization and make the supportedKeySystems() callable from non-main thread.

* Source/WebCore/platform/graphics/gstreamer/eme/CDMThunder.cpp:
(WebCore::CDMFactoryThunder::CDMFactoryThunder):
(WebCore::CDMFactoryThunder::supportedKeySystems const):
* Source/WebCore/platform/graphics/gstreamer/eme/CDMThunder.h:

Canonical link: https://commits.webkit.org/296122@main

Author: philn

Source/WebCore/platform/graphics/gstreamer/eme/CDMThunder.cpp

@@ -114,24 +114,25 @@ RefPtr<CDMProxy> CDMFactoryThunder::createCDMProxy(const String& keySystem)
     return adoptRef(new CDMProxyThunder(keySystem));
 }
 
-const Vector<String>& CDMFactoryThunder::supportedKeySystems() const
+CDMFactoryThunder::CDMFactoryThunder()
 {
     ASSERT(isMainThread());
 
-    static Vector<String> supportedKeySystems;
-    if (supportedKeySystems.isEmpty()) {
-        std::string emptyString;
-        if (opencdm_is_type_supported(GStreamerEMEUtilities::s_WidevineKeySystem, emptyString.c_str()) == ERROR_NONE)
-            supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_WidevineKeySystem));
-        if (opencdm_is_type_supported(GStreamerEMEUtilities::s_ClearKeyKeySystem, emptyString.c_str()) == ERROR_NONE)
-            supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_ClearKeyKeySystem));
-        if (opencdm_is_type_supported(GStreamerEMEUtilities::s_PlayReadyKeySystems[0], emptyString.c_str()) == ERROR_NONE) {
-            supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_PlayReadyKeySystems[0]));
-            supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_PlayReadyKeySystems[1]));
-        }
-        GST_DEBUG("%zu supported key systems", supportedKeySystems.size());
+    std::string emptyString;
+    if (opencdm_is_type_supported(GStreamerEMEUtilities::s_WidevineKeySystem, emptyString.c_str()) == ERROR_NONE)
+        m_supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_WidevineKeySystem));
+    if (opencdm_is_type_supported(GStreamerEMEUtilities::s_ClearKeyKeySystem, emptyString.c_str()) == ERROR_NONE)
+        m_supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_ClearKeyKeySystem));
+    if (opencdm_is_type_supported(GStreamerEMEUtilities::s_PlayReadyKeySystems[0], emptyString.c_str()) == ERROR_NONE) {
+        m_supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_PlayReadyKeySystems[0]));
+        m_supportedKeySystems.append(String::fromLatin1(GStreamerEMEUtilities::s_PlayReadyKeySystems[1]));
     }
-    return supportedKeySystems;
+    GST_DEBUG("%zu supported key systems", m_supportedKeySystems.size());
+}
+
+const Vector<String>& CDMFactoryThunder::supportedKeySystems() const
+{
+    return m_supportedKeySystems;
 }
 
 bool CDMFactoryThunder::supportsKeySystem(const String& keySystem)

Source/WebCore/platform/graphics/gstreamer/eme/CDMThunder.h

@@ -66,7 +66,8 @@ class CDMFactoryThunder final : public CDMFactory, public CDMProxyFactory {
 
 private:
     friend class NeverDestroyed<CDMFactoryThunder>;
-    CDMFactoryThunder() = default;
+    CDMFactoryThunder();
+    Vector<String> m_supportedKeySystems;
 };
 
 class CDMPrivateThunder final : public CDMPrivate {