Refactor AppDocument to rename name field to documentName.

[vikdubey]

Refactor AppDocument to rename name field to documentName.

flutter/flutter#167426

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[matanlurey]

See comment.

If you'd like to keep iterating on this I can give more pointers.

[matanlurey]

Unfortunately this doesn't really solve the underlying problem, now there is a name and documentName, but you can still use say, task.name and accidentally be referring to the full database/path/to/document instead of task.taskName.

I appreciate the contribution but this isn't enough to warrant merging.

[vikdubey]

Thanks @matanlurey for the prompt review and feedback.

I understand the issue with making both name and documentName accessible. What about we make the name field unaccessible like below,

@OverRide
String? get name {
throw UnsupportedError(
'Accessing name is not allowed. Use documentName instead.');
}

@OverRide
set name(String? value) {
throw UnsupportedError(
'Setting name is not allowed. Use documentName instead.');
}

Please let me know if this would work, I can make code changes accordingly. If not, could you please provide some pointers on potential design. Thanks.

[matanlurey]

Unfortunately that won't be a safe change to make - <Document>.name is used by the underlying (generated) googeapis.v1.firebase package, so it needs to exist, we just don't want to use it (directly). There are a few things we could do, in order of easiest to most difficult:

1. Mark String get/set name as @protected. Firebase APIs can still use, we won't (at least not by accident)
2. Make AppDocument no longer implement/extend Document, and instead using composition

Given the work you already did on this PR, I'd be OK with going with (1) as a stop-gap (it makes the current situation better), and leaving a bug open for (2). What do you think?