* 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
#include "ui/wm/core/shadow_types.h"
#include "ui/wm/core/window_util.h"
#if defined(USE_X11)
#include "atom/browser/browser.h"
#include "atom/browser/ui/views/frameless_view.h"
#include "atom/browser/ui/views/global_menu_bar_x11.h"
#include "atom/browser/ui/views/native_frame_view.h"
#include "atom/browser/ui/x/event_disabler.h"
#include "atom/browser/ui/x/window_state_watcher.h"
#include "atom/browser/ui/x/x_window_utils.h"
#include "base/strings/string_util.h"
#include "chrome/browser/ui/libgtkui/unity_service.h"
#include "ui/base/x/x11_util.h"
#include "ui/gfx/x/x11_types.h"
#include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
#include "ui/views/window/native_frame_view.h"
#elif defined(OS_WIN)
#include "atom/browser/ui/views/win_frame_view.h"
#include "atom/browser/ui/win/atom_desktop_native_widget_aura.h"
#include "atom/browser/ui/win/atom_desktop_window_tree_host_win.h"
#include "skia/ext/skia_utils_win.h"
#include "ui/base/win/shell.h"
#include "ui/display/display.h"
#include "ui/display/screen.h"
#include "ui/display/win/screen_win.h"
#include "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
#endif
namespace atom {
namespace {
#if defined(OS_WIN)