[camera_web] Don't require enumerating cameras on web

[kristoffer-zliide]

Enumerating available cameras on web requires permission and activates hardware. This PR allows initializing the camera controller without having to enumerate available cameras first.

flutter/flutter#145541

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• I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
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• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is [test-exempt].
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[kristoffer-zliide]

At the time of this writing, a version of the example app where the enumeration of availableCameras have been replaced with

 _cameras = <CameraDescription>[
const CameraDescription(
name: 'Front',
lensDirection: CameraLensDirection.front,
sensorOrientation: 0,
),
const CameraDescription(
name: 'Back',
lensDirection: CameraLensDirection.back,
sensorOrientation: 0,
),
];

can be tried out here. Note that, contrary to the normal example app, it doesn't ask for permission before you tap on a camera.

[QoLTech]

Yes, please.

We're creating an application that uses the camera and we're baffled that we need to show a permission dialog to get the list of camera devices. We also noticed that devices with many cameras take a longer time to initialize and display a preview.

[stuartmorgan-g]

Are the changes in this file because the example had an existing issue, or is the web change breaking to clients?

[stuartmorgan-g]

@kristoffer-zliide This appears to be failing web tests in CI (web_platform_tests_shard_2)

@ditman It looks like this is otherwise waiting for your review.

[stuartmorgan-g]

From triage: @kristoffer-zliide Are you planning on fixing the failing tests in this PR?

[stuartmorgan-g]

Marking as a draft pending resolution of the test failures.

[kristoffer-zliide]

@stuartmorgan: The tests are passing now.

[stuartmorgan-g]

• I updated pubspec.yaml with an appropriate new version according to the [pub versioning philosophy], or this PR is [exempt from version changes].
• I updated CHANGELOG.md to add a description of the change, [following repository CHANGELOG style].

Please note that the PR won't be able to land without these steps, which is why they are in the checklist, and not doing it before review will add another round to the review process since things like the CHANGELOG wording are part of the review.

[ditman]

This will need to land until after the camera migration to package:web, but the transition to the new version shouldn't be too painful (🤞)

[stuartmorgan-g]

@ditman Has that transition happened? If not, is there a tracking issue we can link to?

[ditman]

@stuartmorgan actually, yes, camera_web is in package:web since this PR:

• [camera_web] Migrate to package:web #7012

[ditman]

After merging main, it turns out I don't have permissions to push changes to this PR:

ERROR: Permission to zliide/flutter_packages.git denied to ditman.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.

I'll try to refresh this branch so it can land. Thanks for the contribution @kristoffer-zliide, and apologies for the delay in the review! (x_x)

---

(@kristoffer-zliide I can move the changes to a new branch, if you'd prefer)

[stuartmorgan-g]

@kristoffer-zliide Are you still planning on updating this PR based on the review feedback?

[kristoffer-zliide]

I think I'm done here. Sorry if I wasted your time. Feel free to rebase/cherry-pick the four commits onto your own branches.