Change PushSubscription.curve25519dh to PushSubscription.getKey()

Source/modules/push_messaging/PushSubscription.cpp

Index: Source/modules/push_messaging/PushSubscription.cpp
diff --git a/Source/modules/push_messaging/PushSubscription.cpp b/Source/modules/push_messaging/PushSubscription.cpp
index bbe326a8722e291a3379b0ff8bf09a0e12e94815..a1704fbeaaa286459c401e35d8e1fd5f100ace25 100644
--- a/Source/modules/push_messaging/PushSubscription.cpp
+++ b/Source/modules/push_messaging/PushSubscription.cpp
@@ -51,6 +51,14 @@ PassRefPtr<DOMArrayBuffer> PushSubscription::curve25519dh() const
     return m_curve25519dh;
 }
 
+PassRefPtr<DOMArrayBuffer> PushSubscription::getKey(const AtomicString& name) const
+{
+    if (name == "curve25519dh")
+        return m_curve25519dh;
+
+    return nullptr;
+}
+
 ScriptPromise PushSubscription::unsubscribe(ScriptState* scriptState)
 {
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);