update_engine: Rename "chromeos" -> "brillo" in include paths and namespaces

libchromeos is transitioning to libbrillo and chromeos namespaces
and include directory is changing to brillo.

Bug: 24872993
Change-Id: I770659a95be380a50fe3b2ba9f91d65818f40945
diff --git a/update_manager/update_manager-inl.h b/update_manager/update_manager-inl.h
index 2f6b603..77224cf 100644
--- a/update_manager/update_manager-inl.h
+++ b/update_manager/update_manager-inl.h
@@ -22,7 +22,7 @@
 
 #include <base/bind.h>
 #include <base/location.h>
-#include <chromeos/message_loops/message_loop.h>
+#include <brillo/message_loops/message_loop.h>
 
 #include "update_engine/update_manager/evaluation_context.h"
 
@@ -157,7 +157,7 @@
   base::Closure eval_callback = base::Bind(
       &UpdateManager::OnPolicyReadyToEvaluate<R, ExpectedArgs...>,
       base::Unretained(this), ec, callback, policy_method, args...);
-  chromeos::MessageLoop::current()->PostTask(FROM_HERE, eval_callback);
+  brillo::MessageLoop::current()->PostTask(FROM_HERE, eval_callback);
 }
 
 }  // namespace chromeos_update_manager