conditionally add back line break in feedback dialog

I realized that the line break that I removed in my previous commit was there so that in the share dialog we had a line break between the sharing buttons and the continue/try again buttons.  This adds back the break for that case, while still keeping it removed for the standard "continue" dialog".
![image](https://cloud.githubusercontent.com/assets/1767466/2684854/29eb21ae-c1bf-11e3-9abf-2fd9fbb9559f.png)