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### Problem Description
I need a way of checking if the user is in https://i.imgur.com/yvZYfsG.png
Windows Dark mode or light mode

### Proposed Solution
systemPreferences.getShellColorType()

### Alternatives Considered
n/a

### Additional Information
Because my app icon is white, I want it to invert if using the Windows 10 light mode.
https://i.imgur.com/dzsLQTs.png
You can barely see it in light mode.

shell/browser/api/atom_api_system_preferences.cc
.SetMethod("subscribeLocalNotification",
                 &SystemPreferences::SubscribeLocalNotification)
      .SetMethod("unsubscribeLocalNotification",
                 &SystemPreferences::UnsubscribeLocalNotification)
      .SetMethod("postWorkspaceNotification",
                 &SystemPreferences::PostWorkspaceNotification)
      .SetMethod("subscribeWorkspaceNotification",
                 &SystemPreferences::SubscribeWorkspaceNotification)
      .SetMethod("unsubscribeWorkspaceNotification",
                 &SystemPreferences::UnsubscribeWorkspaceNotification)
      .SetMethod("registerDefaults", &SystemPreferences::RegisterDefaults)
      .SetMethod("getUserDefault", &SystemPreferences::GetUserDefault)
      .SetMethod("setUserDefault", &SystemPreferences::SetUserDefault)
      .SetMethod("removeUserDefault", &SystemPreferences::RemoveUserDefault)
      .SetMethod("isSwipeTrackingFromScrollEventsEnabled",
                 &SystemPreferences::IsSwipeTrackingFromScrollEventsEnabled)
      .SetMethod("getEffectiveAppearance",
                 &SystemPreferences::GetEffectiveAppearance)
      .SetMethod("_getAppLevelAppearance",
                 &SystemPreferences::GetAppLevelAppearance)
      .SetMethod("_setAppLevelAppearance",
                 &SystemPreferences::SetAppLevelAppearance)
      .SetProperty("appLevelAppearance",
                   &SystemPreferences::GetAppLevelAppearance,
                   &SystemPreferences::SetAppLevelAppearance)
      .SetMethod("getSystemColor", &SystemPreferences::GetSystemColor)
      .SetMethod("canPromptTouchID", &SystemPreferences::CanPromptTouchID)
      .SetMethod("promptTouchID", &SystemPreferences::PromptTouchID)
      .SetMethod("isTrustedAccessibilityClient",
                 &SystemPreferences::IsTrustedAccessibilityClient)