* Output of `node_modules/.bin/electron --version`: v3.0.10
* Operating System (Platform and Version): Windows 10 x64 (1803  17134.345)
* Output of `node_modules/.bin/electron --version` on last known working Electron version (if applicable):
v3.0.10
**Expected Behavior**
I would like to see the window move across the screen.

**Actual behavior**
The window moves around the screen. But first, the height of the window decreases.

**To Reproduce**
Write simple program that contains code:
`
mainWindow = new BrowserWindow({ width: 370,
		height: 270,
		x: 100,
		y: 100,
		resizable: false,
	 });
`
Start app. Grab the window with the mouse for its title and drag across the screen.

**Additional Information**
This error occurs when explicitly specifying the x, y coordinates of the window and the option "resizable: false".

atom/browser/ui/views/root_view.cc
#include "atom/browser/ui/views/root_view.h"
#include "atom/browser/native_window.h"
#include "atom/browser/ui/views/menu_bar.h"
#include "content/public/browser/native_web_keyboard_event.h"
namespace atom {
namespace {
#if defined(OS_WIN)
const int kMenuBarHeight = 20;
#else
const int kMenuBarHeight = 25;
#endif
bool IsAltKey(const content::NativeWebKeyboardEvent& event) {
  return event.windows_key_code == ui::VKEY_MENU;
}
bool IsAltModifier(const content::NativeWebKeyboardEvent& event) {
  typedef content::NativeWebKeyboardEvent::Modifiers Modifiers;
  int modifiers = event.GetModifiers();
  modifiers &= ~Modifiers::kNumLockOn;
  modifiers &= ~Modifiers::kCapsLockOn;
  return (modifiers == Modifiers::kAltKey) ||
         (modifiers == (Modifiers::kAltKey | Modifiers::kIsLeft)) ||
         (modifiers == (Modifiers::kAltKey | Modifiers::kIsRight));
}
}  
RootView::RootView(NativeWindow* window)