Revert "Fix NPE which occurs when MediaBrowserService.onLoadItem gives null"

This changed caused test to fail on API 17.
https://sponge.corp.google.com/target?id=224eedaf-78ae-470b-ae8f-7e098db37e33&target=android.support.mediacompat.test&searchFor=&show=FAILED&sortBy=STATUS


This reverts commit a6d8d0b69c9129c7ab412c82b483a600ef9ef1ac.

Change-Id: I7391b5d3b2f094341399b3db2192a9be6e95bf1f
4 files changed