Modify the impl of ThreadList::GetSelectedThread() so that it tries to fetch the m_selected_tid thread first, check to see if it is valid (might be null if the thread just exited), and if not select/return the 0th thread instead.
Modify the impl of ThreadList::GetSelectedThread() so that it tries to fetch the
m_selected_tid thread first, check to see if it is valid (might be null if the
thread just exited), and if not select/return the 0th thread instead.


git-svn-id: b33bab8abb5b18c12ee100cd7761ab452d00b2b0@138591 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb