setTypeExtension 1031 Source/core/dom/Element.cpp         CustomElementRegistrationContext::setTypeExtension(this, newValue);
setTypeExtension  122 Source/core/dom/custom/CustomElementRegistrationContext.cpp     setTypeExtension(element, type);
setTypeExtension   62 Source/core/dom/custom/CustomElementRegistrationContext.h     static void setTypeExtension(Element*, const AtomicString& type);