DO NOT MERGE: moving uiautomatorviewer into sdk

It's currently under frameworks/testing

This is cherry-pick'd back to ensure that all branches have a
copy of uiautomatorviewer

Change-Id: I8444f5c375a605c8c6480a33cee19a6d3d5ad7ca
merge in jb-mr0-release history after reset to jb-dev
Merge android-4.1.2_r1