Flip Linux ChromeOS trybot to GN

third_party/libXNVCtrl/BUILD.gn

Index: third_party/libXNVCtrl/BUILD.gn
diff --git a/third_party/libXNVCtrl/BUILD.gn b/third_party/libXNVCtrl/BUILD.gn
index ef95a0dd37be5e57be2713595d8933fd19164daf..949401a2367c9592568687efbb6802ac152f63ae 100644
--- a/third_party/libXNVCtrl/BUILD.gn
+++ b/third_party/libXNVCtrl/BUILD.gn
@@ -2,6 +2,17 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+# This warning disable must be appended to the command line after the general
+# warnings setup, so must be in a config.
+config("libXNVCtrl_config") {
+  # This will build under most configurations with this warning enabled, but
+  # some older system headers are missing a "const" on the third parameter of
+  # XextAddDisplay which will cause a failure.
+  cflags = [
+    "-Wno-incompatible-pointer-types-discards-qualifiers",
+  ]
+}
+
 source_set("libXNVCtrl") {
   sources = [
     "NVCtrl.c",
@@ -9,4 +20,9 @@ source_set("libXNVCtrl") {
     "NVCtrlLib.h",
     "nv_control.h",
   ]
+
+  configs += [
+    ":libXNVCtrl_config",
+    "//build/config/linux:x11",
+  ]
 }