feat: expose app accessibility transparency settings api (#40073)

docs/api/system-preferences.md

@@ -435,6 +435,10 @@ Returns an object with system animation settings.
 
 ## Properties
 
+### `systemPreferences.accessibilityDisplayShouldReduceTransparency()` _macOS_
+
+A `boolean` property which determines whether the app avoids using semitransparent backgrounds. This maps to [NSWorkspace.accessibilityDisplayShouldReduceTransparency](https://developer.apple.com/documentation/appkit/nsworkspace/1533006-accessibilitydisplayshouldreduce)
+
 ### `systemPreferences.appLevelAppearance` _macOS_ _Deprecated_
 
 A `string` property that can be `dark`, `light` or `unknown`. It determines the macOS appearance setting for

shell/browser/api/electron_api_system_preferences.cc

@@ -110,6 +110,9 @@ gin::ObjectTemplateBuilder SystemPreferences::GetObjectTemplateBuilder(
       .SetMethod("isTrustedAccessibilityClient",
                  &SystemPreferences::IsTrustedAccessibilityClient)
       .SetMethod("askForMediaAccess", &SystemPreferences::AskForMediaAccess)
+      .SetProperty(
+          "accessibilityDisplayShouldReduceTransparency",
+          &SystemPreferences::AccessibilityDisplayShouldReduceTransparency)
 #endif
       .SetMethod("getAnimationSettings",
                  &SystemPreferences::GetAnimationSettings);

shell/browser/api/electron_api_system_preferences.h

@@ -96,6 +96,7 @@ class SystemPreferences
                       gin::Arguments* args);
   void RemoveUserDefault(const std::string& name);
   bool IsSwipeTrackingFromScrollEventsEnabled();
+  bool AccessibilityDisplayShouldReduceTransparency();
 
   std::string GetSystemColor(gin_helper::ErrorThrower thrower,
                              const std::string& color);

shell/browser/api/electron_api_system_preferences_mac.mm

@@ -653,4 +653,9 @@ void SystemPreferences::SetAppLevelAppearance(gin::Arguments* args) {
   }
 }
 
+bool SystemPreferences::AccessibilityDisplayShouldReduceTransparency() {
+  return [[NSWorkspace sharedWorkspace]
+      accessibilityDisplayShouldReduceTransparency];
+}
+
 }  // namespace electron::api