shill: 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
TEST=built for aosp and brillo, all unit tests pass on dragonboard

Change-Id: I804311e49ee780ca96e05f6a581e8c95709d4e1d
diff --git a/test_event_dispatcher.h b/test_event_dispatcher.h
index aaaa397..b147990 100644
--- a/test_event_dispatcher.h
+++ b/test_event_dispatcher.h
@@ -19,7 +19,7 @@
 
 #include <base/macros.h>
 #include <base/message_loop/message_loop.h>
-#include <chromeos/message_loops/base_message_loop.h>
+#include <brillo/message_loops/base_message_loop.h>
 
 #include "shill/event_dispatcher.h"
 
@@ -37,7 +37,7 @@
   // Message loop for testing.
   base::MessageLoopForIO message_loop_;
   // The chromeos wrapper for the main message loop.
-  chromeos::BaseMessageLoop chromeos_message_loop_{&message_loop_};
+  brillo::BaseMessageLoop chromeos_message_loop_{&message_loop_};
 
   DISALLOW_COPY_AND_ASSIGN(EventDispatcherForTest);
 };