[camera] Add `isDisposed` getter to `CameraController`

[Dampfwalze]

Add isDisposed getter to CameraController

Solves https://github.com/flutter/flutter/issues/141513

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[Dampfwalze]

I am sorry, while editing it magicaly submitted by itself. I wasn't done...

[stuartmorgan]

@Dampfwalze Is this ready for review? From the comments above it's not clear.

[Dampfwalze]

Yes, it is ready for review. Sorry, I messed up a bit.

[stuartmorgan]

My understanding is that historically we have deliberately avoided adding public isDisposed methods to classes in Flutter, because an object shouldn't be disposed until it's no longer being referenced. I would strongly prefer we not be inconsistent with Flutter patterns.

The linked issue requested further clarification of why you needed this, and it timed out without any response on this question. Please file a new issue further explaining (with detailed code samples) why you can't just null out your references to the object.

[stuartmorgan]

The linked issue requested further clarification of why you needed this, and it timed out without any response on this question. Please file a new issue further explaining (with detailed code samples) why you can't just null out your references to the object.

Absent an answer to this question, this is not something we would move forward with; closing.