Sprite Editor - changing between the blue and green borders does not feel instant on Mac OS X compared to Windows.

To reproduce:
- Open attached project
- Select the texture file
- If it is not already > change its import settings to Sprite
- Select Single or Multiple
- Click the Sprite Editor button
- Observe one of the two behaviors when the Sprite Editor window opens:

1. Sprite is represented with a blue border, but no dots on the corners (see attached screen shot)
2. There are no blue borders, so user has to draw the borders on the sprite

- When the blue borders are present, press 'control' on keyboard and observe that it takes 1-2 seconds to change to the green border. And if it does not change, user has to click in the Sprite window to make the green border appear.