Fix an issue where scripted commands would not actually print any of their output if an immediate output file was set in the result object via a Python file object

Fixes rdar://24130303

llvm-svn: 257644
diff --git a/lldb/source/Host/common/File.cpp b/lldb/source/Host/common/File.cpp
index 71a6149..a862f2c 100644
--- a/lldb/source/Host/common/File.cpp
+++ b/lldb/source/Host/common/File.cpp
@@ -399,6 +399,15 @@
     return error;
 }
 
+void
+File::Clear ()
+{
+    m_stream = nullptr;
+    m_descriptor = -1;
+    m_options = 0;
+    m_own_stream = false;
+    m_is_interactive = m_supports_colors = m_is_real_terminal = eLazyBoolCalculate;
+}
 
 Error
 File::GetFileSpec (FileSpec &file_spec) const