[camera] Support image streams on Windows platform

[jlundOverlay]

Adds support to the to the camera plugin for streaming frames on windows as implemented in #7067

Fixes flutter/flutter#97542

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[jlundOverlay]

Are we better off just removing the assertion all together, seems redundant to limit what non federated packages can do?

[loic-sharma]

Looks great - thanks for the contribution!

For second reviewer: don't merge until #7067 lands and camera_windows 0.2.5 is published.

[loic-sharma]

Are we better off just removing the assertion all together, seems redundant to limit what non federated packages can do?

Excellent question. Personally, I think it's good to keep these checks. This tells app developers if they use an API that's unsupported on a specific platform, which is a common mistake. If a federated platform package wants to add a feature, they can ask us to remove a particular check to allowlist them.

[bparrishMines]

LGTM (it also looks like the windows implementation has landed)

Are we better off just removing the assertion all together, seems redundant to limit what non federated packages can do?

Typically you would be correct, but the camera plugin still uses a default implementation for CameraPlatform. For newer plugins, we don't add this check since the platform interface would throw an error by default if the method wasn't supported.

[cbracken]

Looks like this needs to be rebased and merge conflicts fixed. #7067 has landed, so I'm assuming once that's done, we're close to landing this?

[stuartmorgan-g]

@jlundOverlay Are you still planning on updating this PR?

[jlundOverlay]

Have fixed the merge conflicts, should be good to go.

[stuartmorgan-g]

Looking at this PR in more detail: it does not appear that the bug I flagged here was ever fixed. We should not enable this feature when it will fail to send responses and violate the contract of the engine APIs it uses.

[stuartmorgan-g]

Are we better off just removing the assertion all together, seems redundant to limit what non federated packages can do?

Excellent question. Personally, I think it's good to keep these checks. This tells app developers if they use an API that's unsupported on a specific platform, which is a common mistake. If a federated platform package wants to add a feature, they can ask us to remove a particular check to allowlist them.

We should fix this via this pattern which is our preferred approach; the hard-coded platform checks are a legacy of pre-federation approaches. Rather than update the hard-coding, the much better fix here would be to add a new platform interface method to query for streaming support, update the supported platforms to return true for it, and then update the app-facing package to require those minimum versions of the implementation packages (to avoid regressions) and gate on that check instead of platform.

[stuartmorgan-g]

@jlundOverlay Are you still planning on updating this to address the issue with missing responses?

If not, we should revert the underlying PR, as that code is not correct, and would cause serious issues if ever exposed.

[gamelaster]

@yoongyo it seems as the original author of patch was doing that as part of their job, and maybe they don't work anymore. I think it would be wise to look for someone, who can continue working on this.

Of course, writing this is easy, but I already tried to put this into my job's todo-list, although, in the end, we will not use this feature ☹️ .

[stuartmorgan-g]

Closing in light of #7951 and the lack of response here. If you decided to revisit this feature in the future, please feel free to open a new PR!