Remove WebFrame::canHaveSecureChild

To simplify the public API, ServiceWorkerNetworkProvider can do the
parent walk itself.

Follow-up to https://crrev.com/ad1850962644e19.

BUG=607543

Review-Url: https://codereview.chromium.org/2082493002
Cr-Commit-Position: refs/heads/master@{#400896}
DEFINE_TRACE_WRAPPERS(Document)
{
    visitor->traceWrappers(m_importsController);
    visitor->traceWrappers(m_implementation);
    visitor->traceWrappers(m_styleSheetList);
    visitor->traceWrappers(m_styleEngine);
    visitor->traceWrappers(
        Supplementable<Document>::m_supplements.get(
            FontFaceSet::supplementName()));
    for (int i = 0; i < numNodeListInvalidationTypes; ++i) {
        for (auto list : m_nodeLists[i]) {
            visitor->traceWrappers(list);
        }
    }
    ContainerNode::traceWrappers(visitor);
}

DEFINE_TRACE_WRAPPERS(Document)
{
    visitor->traceWrappers(m_importsController);
    visitor->traceWrappers(m_implementation);
    visitor->traceWrappers(m_styleSheetList);
    visitor->traceWrappers(m_styleEngine);
    visitor->traceWrappers(
        Supplementable<Document>::m_supplements.get(
            FontFaceSet::supplementName()));
    for (int i = 0; i < numNodeListInvalidationTypes; ++i) {
        for (auto list : m_nodeLists[i]) {
            visitor->traceWrappers(list);
        }
    }
    ContainerNode::traceWrappers(visitor);
}
