change header graphic - great way to get a quick 10 rating

This is a great way to land yourself your first 10 rating or another one very quickly I currently have 2 graphics 1. Is a white header graphic with rounded corners and transparent background 2. A regular rectangle graphic says android on it. When I placed the graphic on top of the white one because its rectangluar it covers up the transparent corners. I need this android one to fit into the white cornered graphic as the white cornered one is exact to my website. Yet I need to have this fit inside without any white from the one behind showing. So basically at the end i should have exactly what i have in the white graphic but it will be the android design. I wish I knew how to cut off the corners exactly like the white one has been done as that is the trick im sure it is. So A. I need you to do it B. I need you to tell me the exact steps of how you did it. Files are attached in zip