Fix regression of test SourceManagerTestCase.test_display_source_python.

llvm-svn: 141021
diff --git a/lldb/source/API/SBSourceManager.cpp b/lldb/source/API/SBSourceManager.cpp
index 64b8e54..76f58b7 100644
--- a/lldb/source/API/SBSourceManager.cpp
+++ b/lldb/source/API/SBSourceManager.cpp
@@ -51,7 +51,7 @@
                                            const char* current_line_cstr,
                                            lldb_private::Stream *s)
         {
-            if (file)
+            if (!file)
                 return 0;
             
             if (m_debugger_sp)