LLDB exits the command interpreter and thus LLDB when using a pty or file as the input handle and a blank line is entered (like when running under emacs). This is now fixed.

<rdar://problem/15976187>



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@200790 91177308-0d34-0410-b5e6-96231b3b80d8