Fix standalone Linux build

src/tests/gl_tests/VulkanFormatTablesTest.cpp

@@ -7,13 +7,18 @@
 //   Tests to validate our Vulkan support tables match hardware support.
 //
 
+#include "test_utils/ANGLETest.h"
+#include "test_utils/angle_test_instantiate.h"
+// 'None' is defined as 'struct None {};' in
+// third_party/googletest/src/googletest/include/gtest/internal/gtest-type-util.h.
+// But 'None' is also defined as a numeric constant 0L in <X11/X.h>.
+// So we need to include ANGLETest.h first to avoid this conflict.
+
 #include "libANGLE/Context.h"
 #include "libANGLE/angletypes.h"
 #include "libANGLE/formatutils.h"
 #include "libANGLE/renderer/vulkan/ContextVk.h"
 #include "libANGLE/renderer/vulkan/RendererVk.h"
-#include "test_utils/ANGLETest.h"
-#include "test_utils/angle_test_instantiate.h"
 
 using namespace angle;