ART: Include cleanup

Let clang-format reorder the header includes.

Derived with:

* .clang-format:
 BasedOnStyle: Google
 IncludeIsMainRegex: '(_test|-inl)?$'

* Steps:
 find . -name '*.cc' -o -name '*.h' | xargs sed -i.bak -e 's/^#include/ #include/' ; git commit -a -m 'ART: Include cleanup'
 git-clang-format -style=file HEAD^
 manual inspection
 git commit -a --amend

Test: mmma art
Change-Id: Ia963a8ce3ce5f96b5e78acd587e26908c7a70d02
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 9e3e76c..c5e11f1 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -16,6 +16,8 @@
 
 #include "class_linker.h"
 
+#include <unistd.h>
+
 #include <algorithm>
 #include <deque>
 #include <iostream>
@@ -24,7 +26,6 @@
 #include <queue>
 #include <string>
 #include <tuple>
-#include <unistd.h>
 #include <unordered_map>
 #include <utility>
 #include <vector>