Add trace-to-file support for base::TestSuite

base/test/test_suite.h

Index: base/test/test_suite.h
diff --git a/base/test/test_suite.h b/base/test/test_suite.h
index 37cad03f992f2e9db95b520c7bf1b32af702141d..fe634a7aca289954517da76a9191f2dc92c6b647 100644
--- a/base/test/test_suite.h
+++ b/base/test/test_suite.h
@@ -12,6 +12,7 @@
 #include <string>
 
 #include "base/at_exit.h"
+#include "base/debug/trace_to_file.h"
 #include "base/memory/scoped_ptr.h"
 
 namespace testing {
@@ -80,6 +81,8 @@ class TestSuite {
   // Basic initialization for the test suite happens here.
   void PreInitialize(bool create_at_exit_manager);
 
+  debug::TraceToFile trace_to_file_;
+
   bool initialized_command_line_;
 
   DISALLOW_COPY_AND_ASSIGN(TestSuite);