Default Question about XT926 part

So, I've bought my RAZR MAXX HD a few weeks ago and have been overall happy.
I've tried a new cape today, and I noticed the front part of my screen was popping out...
I took it off and ended up with this in my hand, and the "actual" screen of the device showing.
The actual screen was pretty scuffed up so I decided I would continue to use the part that came off.
My question is: this part has some glue that allows it to stick to the actual phone . If I buy a new part online, like so, where do I get the proper glue, so it doesn't damage the actual screen?

Thanks!

HTC Sensation Z710e