[camera] - Fix component CameraPreview on Flutter use impeller

[jhonathanqz]

Fixed CameraPreview component, because after updating Flutter to impiller, it was mirroring the camera preview.

Below is the link to the open ISSUE that this PR attempts to resolve.
flutter/flutter#156974

List which issues are fixed by this PR. You must list at least one issue.

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[stuartmorgan]

Thanks for the contribution! You haven’t checked off any of the items in the PR checklist above, so I’m assuming this is a work in progress and am marking it as a Draft. Please review the checklist, updating the PR as appropriate, and when that’s complete please feel free to mark the PR as ready for review.

[jhonathanqz]

@stuartmorgan I have already updated the PR and requested a review again. The PR corrects the CameraPreview component referring to the [camera] package, because when Flutter started using [impeller] the camera preview had a mirrored effect.

[stuartmorgan]

• I linked to at least one issue that this PR fixes in the description above.

I don't see any issue links in the PR description; please see step 2 in the destination of the linked documentation about our PR process.

• I added new tests to check the change I am making, or this PR is test-exempt.

This will need a test. The fact that this is being done unconditionally in the cross-platform code when camera supports platforms that always use impeller, platforms that never use impeller, and platforms that may or may not use impeller depending on the Flutter version and user-provided flags seems unexpected, so tests that validate this on all platforms camera supports will be important.

[jhonathanqz]

@stuartmorgan
I modified the code to use this mirroring correction only for Android and iOS platforms.
The link to an open issue with this problem was also mentioned in the header.

[stuartmorgan]

I modified the code to use this mirroring correction only for Android and iOS platforms.

Platform-specific code generally does not belong in the app-facing package. The issue of assuming that impeller is enabled in all cases on those platforms is also not addressed by that change.

Also, this still needs tests, per Flutter policy, as described in the contributing docs.