Merge "iorap: Add a DEBUG guide on IORap debugging log." into rvc-qpr-dev am: 4b0ec66e83 am: 396ef95fff

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/13001653

Change-Id: I26317133027794c2dfb2a6df1952184b06800f13