From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jeremy Apthorp <nornagon@nornagon.net>
Date: Thu, 20 Sep 2018 17:49:24 -0700
Subject: mas-cgdisplayusesforcetogray.patch

Removes usage of the CGDisplayUsesForceToGray private API.

diff --git a/ui/display/mac/screen_mac.mm b/ui/display/mac/screen_mac.mm
index 4d5b83a1a4b0c1d03378ab1aae8ef43935c387d3..463ff7105ac329cafed793fd87cfc8423e0a0ed7 100644
--- a/ui/display/mac/screen_mac.mm
+++ b/ui/display/mac/screen_mac.mm
@@ -107,7 +107,17 @@ Display BuildDisplayForScreen(NSScreen* screen) {
 
   display.set_color_depth(NSBitsPerPixelFromDepth([screen depth]));
   display.set_depth_per_component(NSBitsPerSampleFromDepth([screen depth]));
+#ifdef MAS_BUILD
+  // This is equivalent to the CGDisplayUsesForceToGray() API as at 2018-08-06,
+  // but avoids usage of the private API.
+  CFStringRef app = CFSTR("com.apple.CoreGraphics");
+  CFStringRef key = CFSTR("DisplayUseForcedGray");
+  Boolean key_valid = false;
+  display.set_is_monochrome(
+      CFPreferencesGetAppBooleanValue(key, app, &key_valid));
+#else
   display.set_is_monochrome(CGDisplayUsesForceToGray());
+#endif
 
   // CGDisplayRotation returns a double. Display::SetRotationAsDegree will
   // handle the unexpected situations were the angle is not a multiple of 90.
