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* Electron version: 1.6.10
* Operating system: Windows 7

### Expected behavior

<!-- What do you think should happen? -->

Notification size should be smaller, similar to the one you can just see in the screenshot below that you can just see the bottom of, behind the large notification.


### Actual behavior

<!-- What actually happens? -->

The new notifications for windows 7 are taking up half of the screen space as seen in the image below:
![image](https://cloud.githubusercontent.com/assets/5689874/26761521/f2eec2c4-4928-11e7-9572-6df74ddb7ad1.png)

I'm running windows in parallels on a mac, so I expect it to be a screen resolution issue (2880x1800)



### How to reproduce

Test notifications on Windows 7 with parallels on a mac, or use Windows with a high screen resolution (e.g. 2880x1800).

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brightray/browser/win/win32_desktop_notifications/desktop_notification_controller.cc
auto hinstance = RegisterWndClasses();
    auto hwnd = Toast::Create(hinstance, data);
    if (hwnd) {
        int toast_pos = 0;
        if (!instances_.empty()) {
            auto& item = instances_.back();
            _ASSERT(item.hwnd);
            ScreenMetrics scr;
            auto toast = Toast::Get(item.hwnd);
            toast_pos = toast->GetVerticalPosition() +
                        toast->GetHeight() +
                        scr.Y(toast_margin_<int>);
        }
        instances_.push_back({ hwnd, move(data) });
        if (!hwnd_controller_) {
            
            
            hwnd_controller_ = CreateWindow(class_name_, nullptr, 0,
                                            0, 0, 0, 0,
                                            NULL, NULL, hinstance, this);
        }
        auto toast = Toast::Get(hwnd);
        toast->PopUp(toast_pos);
    }
}
HWND DesktopNotificationController::GetToast(