Merge tag 'android-6.0.0_r26' into HEAD

Android 6.0.0 release 26

* tag 'android-6.0.0_r26':
  update jank test helper
  update tradefed prebuilt for CTS runner
  Create a version of the annotations prebuilt that can be used as a dependency [DO NOT MERGE]
  Update tools-common prebuilts. [DO NOT MERGE]
  Update sdk-common prebuilt. [DO NOT MERGE]
  Update layoutlib_api-prebuilt from 1.3 RC4. [DO NOT MERGE]
  vboot_signer: Fix issues with keyblock

Change-Id: I58e2cbcd84cf1160fd8d8484c16da2625c36bd59