[PoC] Reformat all BUILD.gn and *.gni files with new gn.

mojo/edk/system/BUILD.gn

Index: mojo/edk/system/BUILD.gn
diff --git a/mojo/edk/system/BUILD.gn b/mojo/edk/system/BUILD.gn
index 11a3a8fa3f99594d0fc81677c8061d8c22c85415..90336529e8c0f1ab0b41a3d61d299c788d406e94 100644
--- a/mojo/edk/system/BUILD.gn
+++ b/mojo/edk/system/BUILD.gn
@@ -116,8 +116,8 @@ group("tests") {
   testonly = true
   deps = [
     # TODO(use_chrome_edk): remove "2"
-    ":mojo_system_unittests2",
     ":mojo_message_pipe_perftests2",
+    ":mojo_system_unittests2",
   ]
 }
 
@@ -177,8 +177,8 @@ test("mojo_system_unittests2") {
     ":test_utils",
 
     # TODO(use_chrome_edk): remove "2"
-    "../embedder:embedder_unittests2",
     "../../../mojo/public/cpp/environment:standalone",
+    "../embedder:embedder_unittests2",
     "../test:test_support",
     "//base",
     "//base/test:test_support",
@@ -203,9 +203,9 @@ test("mojo_message_pipe_perftests2") {
 
   deps = [
     ":test_utils",
-    "../test:test_support",
-    "../test:run_all_perftests",
     "../../../mojo/public/cpp/environment:standalone",
+    "../test:run_all_perftests",
+    "../test:test_support",
     "//base",
     "//base/test:test_support",
     "//testing/gtest",