* Electron Version: 2.0.0
* Operating System (Platform and Version): Windows 10
* Last known working Electron version: before commit bb5eecc16cff8053c7b04e0b9396803fbbb8c4df

**Expected Behavior**
Width and height of a window should not change while being dragged 

**Actual behavior**
Width and height become smaller.

**To Reproduce**
Create a window with:
  var mainWindow = new BrowserWindow({width: 1024, height: 880, x: 30, y: 30,
            resizable: false })

Then drag the window.  Width and height become smaller than specified (1024, 880)

**Additional Information**
NativeWindowViews::SetBounds calls SetMin/MaxSize(bounds) when resizable_ is false.  bounds get adjusted to smaller  numbers by WindowBoundsToContentBounds.

shell/browser/native_window_views.cc
const gfx::Rect& bounds) const {
  if (!has_frame())
    return bounds;
  gfx::Rect content_bounds(bounds);
#if defined(OS_WIN)
  HWND hwnd = GetAcceleratedWidget();
  content_bounds.set_size(DIPToScreenRect(hwnd, content_bounds).size());
  RECT rect;
  SetRectEmpty(&rect);
  DWORD style = ::GetWindowLong(hwnd, GWL_STYLE);
  DWORD ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);
  AdjustWindowRectEx(&rect, style, FALSE, ex_style);
  content_bounds.set_width(content_bounds.width() - (rect.right - rect.left));
  content_bounds.set_height(content_bounds.height() - (rect.bottom - rect.top));
  content_bounds.set_size(ScreenToDIPRect(hwnd, content_bounds).size());
#endif
  if (root_view_->HasMenu() && root_view_->IsMenuBarVisible()) {
    int menu_bar_height = root_view_->GetMenuBarHeight();
    content_bounds.set_y(content_bounds.y() + menu_bar_height);
    content_bounds.set_height(content_bounds.height() - menu_bar_height);
  }
  return content_bounds;
}
void NativeWindowViews::UpdateDraggableRegions(