Bug with Thumbnail Creation

[ryanfitzer]

I'm getting a bug in 2.0.7 (I've seen it in earlier versions as well) where the inline uploading process creates different sized thumbnails depending on the image's ratio and/or file size.

Example:
Uploaded an image 1152px wide by 864px tall and WP generated a thumb that was 128px wide by 96px tall.
Uploaded another image that was 576px by 479px and WP generated a thumb that was 96px wide by 73px tall.
Then resized image 2 to be 600px wide by 450px tall and WP generated a thumb that was 128px wide by 96px tall.

WP tries to do some fancy things depending on the aspect ratio of the original image.

I say we just make a thumbnail that fits into an X by X square and let plugins do fancier things.

Attached makes thumbnails fit in 128x128 square and adds hooks.

(In [4751]) Thumbnail creation fixes from mdawaffe. fixes #3588

3588b.diff

This is the functionality I originally intended:

1. wp_thumbnail_creation_size_limit < 0 means make the thumbnail
2. wp_thumbnail_creation_size_limit = 0 means don't make the thumbnail
3. wp_thumbnail_creation_size_limit > 0 means make the thumbnail if image_height * image_width < wp_thumbnail_creation_size_limit

(In [4759]) Thumbnail creation fix from mdawaffe. fixes #3588