[firebase_config] setDefaults option without replace all

[4rthurmonteiro]

What feature would you like to see?

Add the possibility to update setDefaults without replace the old ones if keys aren't the same.

Example:

public Task<Void> setDefaultsAsync(@NonNull Map<String, Object> defaults, @NonNull boolean replace)

if replace false the new parameters will be added with the old ones. If true, it will be replaced.

How would you use it?

I'm using the add-to-app implementation and the host app already has defaults values. But in the flutter side I want add more defaults and I don't want add these defaults in android app code.

I opened a issue in firebase/flutterfire#17620 but firstly this feature must be available in the native SDK.

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.