Make CheckJNI and JNI workarounds mutually exclusive...

...in the opposite direction; needing workarounds turns off CheckJNI.
This isn't necessarily a good idea, but I like the cleanup parts of
this change.

Change-Id: I708235ea3e5cc35ef90b01dd810e097e3ff9dd26
diff --git a/src/trace.cc b/src/trace.cc
index e4be356..6648b85 100644
--- a/src/trace.cc
+++ b/src/trace.cc
@@ -24,6 +24,7 @@
 #include "object_utils.h"
 #include "os.h"
 #include "runtime_support.h"
+#include "scoped_thread_list_lock.h"
 #include "thread.h"