[image_picker] updates to resize logic.

[tarrinneal]

Simplifies resizing logic on ios and android.
Also fixes a bug with resizing flutter/flutter#88901.
Also changes rounding to be closer to original aspect ratio (and consistent across platforms)

fixes flutter/flutter#88901

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[vashworth]

iOS side LGTM.

Suggestion: You could make the width / height calculations into its own method that takes in the originalWidth and originalHeight as arguments. That way you could test the method without needing actual images. I think what you have is fine too, though.

[tarrinneal]

Suggestion: You could make the width / height calculations into its own method that takes in the originalWidth and originalHeight as arguments. That way you could test the method without needing actual images. I think what you have is fine too, though.

That's not a bad idea. I think I'll let the tests stay as they are, since having a more robust "integration" type test is probably good anyway.

[stuartmorgan-g]

LGTM with small comments

[mark8044]

@tarrinneal For whatever reason, this fix doesn't seem to work with images within the gallery that came from a camera photo. This does work perfectly from a photo saved from the web.

A part of me wonders if this has to do with exif metadata and images being landscape vs portrait. I know this was a problem for some time with uploading images to PHP servers which was later fixed in PHP7.x

Scenario 1:

• Take a photo in portrait orientation (normal upright holding of the phone) with large MP size. For example if I snap a photo from a Samsung S21 it saves the image at 3000x4000 pixels

• final List<XFile>? images = await _picker.pickMultiImage(maxWidth: 4032, maxHeight:3024, requestFullMetadata: false);

  DOES NOT WORK. This will return an image sized: 3000x4000

Scenario 2:

• Save a photo that's 3000x4000 pixels to your gallery: https://picsum.photos/3000/4000

• final List<XFile>? images = await _picker.pickMultiImage(maxWidth: 4032, maxHeight:3024, requestFullMetadata: false);

  WORKS. This will return an image sized: 2268x3024