Use fbsource clang-format config

Summary:
This mirrors the clang-format config used by fbsource to Yoga.

They are pretty similar, except for an annoying habit where Yoga's previous forced small functions in headers to be a a single line, so you would get a combination of multiline and single line functions next to each other which are hard to read. That is what motivated this change.

It also enforces header ordering (yay). I don't think we have any side-effect causing headers, so this should be safe.

Reviewed By: yungsters

Differential Revision: D49248994

fbshipit-source-id: 66998395e7c0158ff9d9fb1bee44e8401bdd8f21

tests/YGStyleAccessorsTest.cpp

@@ -5,11 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#include <cstdint>
-#include <type_traits>
 #include <gtest/gtest.h>
 #include <yoga/Yoga.h>
 #include <yoga/style/Style.h>
+#include <cstdint>
+#include <type_traits>
 
 #define ACCESSOR_TESTS_1(NAME, X) \
   style.NAME() = X;               \