Revert "Fix adb hang when subprocess dies early."

This is for http://b/3482112 "adb interactions with device causing test harness failures".

This reverts commit 69c5c4c45bd4f1575ae8bdba13795297be7deb8c.

Change-Id: I630bf2e04d2ecf0223bd2af4e87136754ff880d3
12 files changed