Include the implemented header first in all projects.

The Google C++ style guide dictates that foo.cc and foo_unittest.cc
should include foo.h in the first place, so missing headers in foo.h
are detected with a compile error of the module implementing them and
not when another module uses them.

This CL sweeps across all the .cc file in platform2 enforcing this.

BUG=None
TEST=cbuildbot amd64-generic

Change-Id: I41835835caba13f54c3c844ecf552eb0e47efa9d
Reviewed-on: https://chromium-review.googlesource.com/228894
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Alex Deymo <deymo@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>

buffet/states/state_change_queue_unittest.cc

diff --git a/buffet/states/state_change_queue_unittest.cc b/buffet/states/state_change_queue_unittest.cc
index 7aa6c9f..01f5f9f 100644
--- a/buffet/states/state_change_queue_unittest.cc
+++ b/buffet/states/state_change_queue_unittest.cc
@@ -3,10 +3,10 @@
 // found in the LICENSE file.
 
 
-#include <gtest/gtest.h>
-
 #include "buffet/states/state_change_queue.h"
 
+#include <gtest/gtest.h>
+
 namespace buffet {
 
 class StateChangeQueueTest : public ::testing::Test {