Patch from Andrew Kaylor andrew.kaylor@intel.com to have

Thread::ResetFrameZeroRegisters() clear the UnwindLLDB object when
resetting the thread's register state.

llvm-svn: 167910

lldb/source/Target/Thread.cpp

@@ -1682,6 +1682,8 @@ Thread::ResetFrameZeroRegisters (lldb::DataBufferSP register_data_sp)
         // Clear out all stack frames as our world just changed.
         ClearStackFrames();
         frame_sp->GetRegisterContext()->InvalidateIfNeeded(true);
+        if (m_unwinder_ap.get())
+            m_unwinder_ap->Clear();
 
         return ret;
     }