static void doNotifyFinish(void* context)
{
    BlobResourceHandle* handle = static_cast<BlobResourceHandle*>(context);
    if (!handle->aborted() && handle->client())
        handle->client()->didFinishLoading(handle, 0);

    // Balance the ref() in BlobResourceHandle::notfyFinish().
    handle->deref();
}
static void doNotifyFinish(BlobResourceHandle& handle)
{
    if (handle.aborted())
        return;

    if (!handle.client())
        return;

    handle.client()->didFinishLoading(&handle, 0);
}
static void doNotifyFinish(void* context)
{
    BlobResourceHandle* handle = static_cast<BlobResourceHandle*>(context);
    if (handle->client())
        handle->client()->didFinishLoading(handle, 0);
}