Use Log.w(String, String, Throwable tr) instead of Log.w(String, String)

Use Log.w(String, String, Throwable tr) instead of Log.w(String, String)
to give a bit better performance.

Bug: 160931064
Test: manual verification
Change-Id: I3622f306f706f1cb327c4d974b678b700a1d1d20