I can not comment, do not respond.
After upgrading to the latest build tools, the hierarchy view tool and many other materials were removed from the tool list. I downloaded the tools separately from the Android Studio download page and enabled the hierarchy viewer. Not sure what is going on, but it seems like updating the build tools in Android Studio removes the hierarchy viewer.
: 25.3.0
http://tools.android.com/recent/androidsdktoolsrevision2530feb2017