Update MediaKeySession method names to latest EME spec.

Source/platform/drm/ContentDecryptionModuleSession.cpp

Index: Source/platform/drm/ContentDecryptionModuleSession.cpp
diff --git a/Source/platform/drm/ContentDecryptionModuleSession.cpp b/Source/platform/drm/ContentDecryptionModuleSession.cpp
index 0882ffb429093f746f83f10079b9b79db0e6ed11..cf0df9e451c6cc70948f8ec5172adefd8b7e2f39 100644
--- a/Source/platform/drm/ContentDecryptionModuleSession.cpp
+++ b/Source/platform/drm/ContentDecryptionModuleSession.cpp
@@ -55,9 +55,9 @@ String ContentDecryptionModuleSession::sessionId() const
     return m_session->sessionId();
 }
 
-void ContentDecryptionModuleSession::generateKeyRequest(const String& mimeType, const Uint8Array& initData)
+void ContentDecryptionModuleSession::initialize(const String& mimeType, const Uint8Array& initData)
 {
-    m_session->generateKeyRequest(mimeType, initData.data(), initData.length());
+    m_session->initialize(mimeType, initData.data(), initData.length());
 }
 
 void ContentDecryptionModuleSession::update(const Uint8Array& key)
@@ -65,9 +65,9 @@ void ContentDecryptionModuleSession::update(const Uint8Array& key)
     m_session->update(key.data(), key.length());
 }
 
-void ContentDecryptionModuleSession::close()
+void ContentDecryptionModuleSession::release()
 {
-    m_session->close();
+    m_session->release();
 }
 
 void ContentDecryptionModuleSession::keyAdded()