Setup editorstack's layout

def setup_editorstack(self, parent, layout):
        """Setup editorstack's layout"""
        layout.setSpacing(1)

        self.fname_label = QLabel()
        self.fname_label.setStyleSheet(
            "QLabel {margin: 0px; padding: 3px;}")
        layout.addWidget(self.fname_label)

        menu_btn = create_toolbutton(self, icon=ima.icon('tooloptions'),
                                     tip=_('Options'))
        # Don't show menu arrow and remove padding
        if is_dark_interface():
            menu_btn.setStyleSheet(
                ("QToolButton::menu-indicator{image: none;}\n"
                 "QToolButton{margin: 1px; padding: 3px;}"))
        else:
            menu_btn.setStyleSheet(
                "QToolButton::menu-indicator{image: none;}")
        self.menu = QMenu(self)
        menu_btn.setMenu(self.menu)
        menu_btn.setPopupMode(menu_btn.InstantPopup)
        self.menu.aboutToShow.connect(self.__setup_menu)

        corner_widgets = {Qt.TopRightCorner: [menu_btn]}
        self.tabs = BaseTabs(self, menu=self.menu, menu_use_tooltips=True,
                             corner_widgets=corner_widgets)
        self.tabs.tabBar().setObjectName('plugin-tab')
        self.tabs.set_close_function(self.close_file)
        self.tabs.tabBar().tabMoved.connect(self.move_editorstack_data)
        self.tabs.setMovable(True)

        self.stack_history.refresh()

        if hasattr(self.tabs, 'setDocumentMode') \
           and not sys.platform == 'darwin':
            # Don't set document mode to true on OSX because it generates
            # a crash when the editor is detached from the main window
            # Fixes Issue 561
            self.tabs.setDocumentMode(True)
        self.tabs.currentChanged.connect(self.current_changed)

        if sys.platform == 'darwin':
            tab_container = QWidget()
            tab_container.setObjectName('tab-container')
            tab_layout = QHBoxLayout(tab_container)
            tab_layout.setContentsMargins(0, 0, 0, 0)
            tab_layout.addWidget(self.tabs)
            layout.addWidget(tab_container)
        else:
            layout.addWidget(self.tabs)