[Tizen][Runtime] Always use [tizen_app_id] on tizen.

For xpk, [tizen_app_id] = xwalk.[GenerateId or GenerateIdForPath]
For wgt, [tizen_app_id] = Get from config.xml

And dbus cannot take [tizen_app_id] as object path, we have
to use [package_id] as app's object path on tizen.
if (GetPackageType() == Package::WGT) else if (manifest_->HasKey(keys::kTizenAppIdKey))

If ALL tizen packages are Widget, then the second part would never be reached.

Don't we have any unit tests?