Add a TraceOn(self) method to the base test class, which returns True if we are
currently in trace mode (-t to dotest.py), i.e., tracing the lldb command execution.
Change TestInferiorCrashing.inferior_crashing_python(self) to check this flag in
order to print the stack trace of the inferior thread.

llvm-svn: 129785
diff --git a/lldb/test/lldbtest.py b/lldb/test/lldbtest.py
index 66d4e5c..3c8ea7e 100644
--- a/lldb/test/lldbtest.py
+++ b/lldb/test/lldbtest.py
@@ -951,3 +951,7 @@
             return
 
         print child
+
+    def TraceOn(self):
+        """Returns True if we are in trace mode (i.e., verbose output)."""
+        return traceAlways