Merge tag android-5.1.0_r1 into AOSP_5.1_MERGE

Change-Id: If83121d50c15c11988a2a135356290e82fb9e96e
tree: 1f37d9fab70934d551545689a1a8ba7aeb4c88ff
  1. apps/
  2. build/
  3. util/
  4. .gitignore
  5. README