So your saying its fine to copy Google's I.P. only because it's part of the AOSP... Otherwise it's wrong.. Google could have patented but they give it away for free so its ok.. talk.about double standards..
Copying concepts such as notification center and control center are not the same as copying IP. It has nothing to do with the fact that Android is open source. Google did patent specific implementation details of notification center, however Apple did not use those patented methods.
Look for some primers on copyright law and patent law to gain some understanding about the difference between copying IP and copying unprotected ideas and concepts.