am 7bf1c661: am 034d89d9: docs: cherrypick Change-Id: I3d871d494cf1f626df701efaa43058b66893259e docs: add info about customizing the density of an AVD from command line; and a few editorial things like fix the TOCs

* commit '7bf1c661f1a43236dd075616f4f04a776710dcb0':
  docs: cherrypick Change-Id: I3d871d494cf1f626df701efaa43058b66893259e docs: add info about customizing the density of an AVD from command line; and a few editorial things like fix the TOCs