Since JDK8 b87 I get a bit strange sizing behavior. On the attached screenshots you will find a led control and one image shows the expected visualization (like it was before b87) and the current visualization in b87. It looks like the size is exactly doubled. If you take a look in the attached source code you will find a comment in the LedSkins resize() method which will fix the issue by resizing the control to the half size. I'm not sure but it might be related to the Retina resolution on my Macbook Pro. Unfortunately I have no Windows/Linux machine to test it on.
Please find the files here: https://dl.dropboxusercontent.com/u/84552/tmp/issues/rt-30011.zip
Here are two videos that show the behavior (now in b88): http://t.co/V6lffnfFfu and http://t.co/UNWoa4Gkre
This does not only happen on Custom Controls but every control.