update_engine: Add locations to the MessageLoop calls.

When running the unittests with --v=1, this patch will show the location
where the tasks were posted to the FakeMessageLoop.

BUG=brillo:91
TEST=Ran unittest with --v=1

Change-Id: I0f9b0a3b67a40c26965a396258f1bd45e38f5ba3
Reviewed-on: https://chromium-review.googlesource.com/280568
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
diff --git a/update_manager/evaluation_context.cc b/update_manager/evaluation_context.cc
index 856c5cd..66275de 100644
--- a/update_manager/evaluation_context.cc
+++ b/update_manager/evaluation_context.cc
@@ -10,6 +10,7 @@
 
 #include <base/bind.h>
 #include <base/json/json_writer.h>
+#include <base/location.h>
 #include <base/strings/string_util.h>
 #include <base/values.h>
 
@@ -204,6 +205,7 @@
     DLOG(INFO) << "Waiting for timeout in "
                << chromeos_update_engine::utils::FormatTimeDelta(timeout);
     timeout_event_ = MessageLoop::current()->PostDelayedTask(
+        FROM_HERE,
         base::Bind(&EvaluationContext::OnTimeout,
                    weak_ptr_factory_.GetWeakPtr()),
         timeout);