Add a new driver bug workaround SANDBOX_START_EARLY

build/config/linux/dri/BUILD.gn

Index: build/config/linux/dri/BUILD.gn
diff --git a/build/config/linux/dri/BUILD.gn b/build/config/linux/dri/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..107a5ac98b79bfc0a110866b3139ad996273dcc6
--- /dev/null
+++ b/build/config/linux/dri/BUILD.gn
@@ -0,0 +1,16 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/config/linux/pkg_config.gni")
+
+pkg_config("dri") {
+  packages = [ "dri" ]
+  dri_driver_dir = exec_script(pkg_config_script,
+                               pkg_config_args + [
+                                     "--dridriverdir",
+                                     "dri",
+                                   ],
+                               "string")
+  defines = [ "DRI_DRIVER_DIR=\"$dri_driver_dir\"" ]
+}