* Electron version: 1.4.15
* Operating system: Windows 10

### Actual behavior

Height is oversized by exactly 8px consistently (taskbar is set to small icons).

![Alt](https://raw.githubusercontent.com/adi518/electron-frameless-maximize-test/master/issue.jpg)

### How to reproduce

https://github.com/adi518/electron-frameless-maximize-test
atom/browser/native_window_views.cc
views::Widget* widget, bool active) {
  if (widget != window_.get())
    return;
  
  content::BrowserThread::PostTask(
      content::BrowserThread::UI, FROM_HERE,
      base::Bind(active ? &NativeWindow::NotifyWindowFocus :
                          &NativeWindow::NotifyWindowBlur,
                 GetWeakPtr()));
  if (active && inspectable_web_contents() &&
      !inspectable_web_contents()->IsDevToolsViewShowing())
    web_contents()->Focus();
  
  if (!active && menu_bar_autohide_ && menu_bar_visible_)
    SetMenuBarVisibility(false);
}
void NativeWindowViews::OnWidgetBoundsChanged(
    views::Widget* widget, const gfx::Rect& bounds) {
  if (widget != window_.get())
    return;
  if (widget_size_ != bounds.size()) {
    NotifyWindowResize();
    widget_size_ = bounds.size();
  }
}
void NativeWindowViews::DeleteDelegate() {