Merge "Revert "Precompute cursor indexes in DocumentsUI and improve perf by 2.7%."" into nyc-dev
am: ee6d8be

* commit 'ee6d8be53e1dabf7669150e7e7e39daa58cac542':
  Revert "Precompute cursor indexes in DocumentsUI and improve perf by 2.7%."

Change-Id: I62bb1b479d521b24d1cf1ef05675ba887973867b