I can't replicate the exact phenomenon, but it does seem to show an issue with maximum dimensions.

When I increase the size (even to the 80000000 width) I just get a humongous version of the stretched image.

I'm looking into the conditions of limiting image scale size.

Change 115307 had a related patch set uploaded by Mooeypoo:
[wip] Limit thumbnail dimensions in media edit dialog

https://gerrit.wikimedia.org/r/115307

Change 115307 merged by jenkins-bot:
Limit thumbnail dimensions in media edit dialog

https://gerrit.wikimedia.org/r/115307

I can still reproduce this issue.

Change 115939 had a related patch set uploaded by Mooeypoo:
[wip] Deal with 'none'/'border' and default size in media edit

https://gerrit.wikimedia.org/r/115939

Change 115939 merged by jenkins-bot:
Deal with 'none'/'border' and default size in media edit

https://gerrit.wikimedia.org/r/115939

I can still reproduce this issue for the image :[[File:Dau ho thoi Ho.png]] with Frame and Basic Image type

Another page and image where I encountered this issue: http://en.wikipedia.beta.wmflabs.org/w/index.php?title=Hateres&veaction=edit

I see this image as a huge one. There is a bug here that the context menu is hidden outside the page (should be reported separately) but I don't see this as a dot-size.

Checked under Windows on Chrome version 33.0.1750.146 m and Firefox 27.0.1

In both cases, I see this image as humongous, which is exactly as it appears in the "view" mode.

I can't manage to replicate the "dot-image" effect.

Created attachment 14761
This is how it appears in the review changes in the save dialog

Attached:

I can't replicate here; I set the image even up to "800000000000000000000" width and still it resized as "expected".

Created attachment 14785
Reproduced on windows8-chrome

Attached:

This looks like it's now fixed, I think.