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}
static void assertLayoutTreeUpdated(Node& root)
{
    for (Node& node : NodeTraversal::inclusiveDescendantsOf(root)) {
        if (!node.isElementNode()
            && !node.isTextNode()
            && !node.isShadowRoot()
            && !node.isDocumentNode())
            continue;
        DCHECK(!node.needsStyleRecalc());
        DCHECK(!node.childNeedsStyleRecalc());
        DCHECK(!node.childNeedsDistributionRecalc());
        DCHECK(!node.needsStyleInvalidation());
        DCHECK(!node.childNeedsStyleInvalidation());
        for (ShadowRoot* shadowRoot = node.youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot())
            assertLayoutTreeUpdated(*shadowRoot);
    }
}

static void assertLayoutTreeUpdated(Node& root)
{
    for (Node& node : NodeTraversal::inclusiveDescendantsOf(root)) {
        if (!node.isElementNode()
            && !node.isTextNode()
            && !node.isShadowRoot()
            && !node.isDocumentNode())
            continue;
        DCHECK(!node.needsStyleRecalc());
        DCHECK(!node.childNeedsStyleRecalc());
        DCHECK(!node.childNeedsDistributionRecalc());
        DCHECK(!node.needsStyleInvalidation());
        DCHECK(!node.childNeedsStyleInvalidation());
        for (ShadowRoot* shadowRoot = node.youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot())
            assertLayoutTreeUpdated(*shadowRoot);
    }
}
