Description of Problem:
The scale image dialog sometimes won't recalculate x/y values.

How Reproducible:
100%

Steps to Reproduce:
1. Load an image
2. Get the 'scale image' dialog
3. Delete the x value
4. Delete the y value.
5. Focus on another window
6. Type in a number into the y input box (for example, 768)
7. Press enter.

Actual Results:
The x and y values are set to 1.

Expected Results:
The x value should be calculated based on the aspect ratio and the 
entered y value.

Additional Information: