[GraphicsEnvironment] Add clang-format on GraphicsEnvironment

BUG: N/A
Test: N/A
Change-Id: I63152fc8262d55cf460ea4676b770a51acdf0bc8
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index cd0fbd4..16abc1e 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -4,6 +4,7 @@
 [Builtin Hooks Options]
 # Only turn on clang-format check for the following subfolders.
 clang_format = --commit ${PREUPLOAD_COMMIT} --style file --extensions c,h,cc,cpp
+               libs/graphicsenv/
                libs/gui/
                libs/ui/
                libs/vr/