Replace further questionable HashMap::add usages in bindings

BUG=390928
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/411273002

git-svn-id: svn://svn.chromium.org/blink/trunk@178823 bbb929c8-8fbe-4397-9dbb-9b2b20218538
static v8::Handle<v8::Object> toV8Object(MessagePort* impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
{
    if (!impl)
        return v8::Handle<v8::Object>();
    v8::Handle<v8::Value> wrapper = toV8(impl, creationContext, isolate);
    ASSERT(wrapper->IsObject());
    return wrapper.As<v8::Object>();
}

static v8::Handle<v8::Object> toV8Object(MessagePort* impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
{
    if (!impl)
        return v8::Handle<v8::Object>();
    v8::Handle<v8::Value> wrapper = toV8(impl, creationContext, isolate);
    ASSERT(wrapper->IsObject());
    return wrapper.As<v8::Object>();
}
