Add non-system-border option on Windows

Sine Striker

2023-12-22 c837319767bb609c6ec806336e49a347c77b11d3

 src/core/style/styleagent_win.cpp

@@ -21,27 +21,47 @@
                return false;
            }

            const auto msg = static_cast<const MSG *>(message);
            switch (msg->message) {
                case WM_THEMECHANGED:
                case WM_SYSCOLORCHANGE:
                case WM_DWMCOLORIZATIONCOLORCHANGED: {
                    // TODO: walk through `g_styleAgentSet`
                    break;
                }
            auto themeChanged = [message]() -> bool {
                const auto msg = static_cast<const MSG *>(message);
                switch (msg->message) {
                    case WM_THEMECHANGED:
                    case WM_SYSCOLORCHANGE:
                    case WM_DWMCOLORIZATIONCOLORCHANGED:
                        return true;

                case WM_SETTINGCHANGE: {
                    if (!msg->wParam && msg->lParam &&
                        std::wcscmp(reinterpret_cast<LPCWSTR>(msg->lParam), L"ImmersiveColorSet") ==
                    case WM_SETTINGCHANGE: {
                        if (!msg->wParam && msg->lParam &&
                            std::wcscmp(reinterpret_cast<LPCWSTR>(msg->lParam), L"ImmersiveColorSet") ==
                            0) {
                        // TODO: walk through `g_styleAgentSet`
                            return true;
                        }
                        break;
                    }
                    break;
                }

                default:
                    break;
                    default:
                        break;
                }
                return false;
            }();

            if (themeChanged) {
                auto theme = []() -> StyleAgent::SystemTheme {
                    if (isHighContrastModeEnabled()) {
                        return StyleAgent::HighContrast;
                    } else if (isDarkThemeActive()) {
                        return StyleAgent::Dark;
                    } else {
                        return StyleAgent::Light;
                    }
                }();
                for (auto &&ap : std::as_const(*g_styleAgentSet())) {
                    if (ap->systemTheme != theme) {
                        ap->systemTheme = theme;
                        ap->notifyThemeChanged(theme);
                    }
                }
            }

            return false;
        }

@@ -66,10 +86,16 @@
    SystemSettingEventFilter *SystemSettingEventFilter::instance = nullptr;

    void StyleAgentPrivate::setupSystemThemeHook() {
        if (isHighContrastModeEnabled()) {
            systemTheme = StyleAgent::HighContrast;
        } else if (isDarkThemeActive()) {
            systemTheme = StyleAgent::Dark;
        } else {
            systemTheme = StyleAgent::Light;
        }

        g_styleAgentSet->insert(this);
        SystemSettingEventFilter::install();

        // Initialize `systemTheme` variable
    }

    void StyleAgentPrivate::removeSystemThemeHook() {