[0.78] Add missing loadFromSource method in the DefaultRNFactoryDelegate

[Saadnajmi]

Target Branch(es)

0.78

Link to commit or PR to be picked

facebook/react-native#49931

Description

On both iOS and macOS with the new arch disabled, a new React Native never calls metro to load the bundle, resulting in an empty screen. This is particularly bad on React Native macOS, because we don't fully support the new architecture yet.

[react-native-bot]

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[lxr-mwhite]

Thank you for creating this issue. It appears like this is impacting a lot of React Native project's using the old architecture and it would be great to have this included in patch release.

[cipolleschi]

@react-native-bot merge 8b33668c4338d31c27e6bd90b2a0e6fc0a077588 0.78-stable

[react-native-bot]

✅ Successfully picked up your commit facebook/react-native@8b33668 on the branch https://github.com/facebook/react-native/commits/0.78-stable