reduced vertical space in gui with responsive toolbar buttons (bug #53902) * gui-preferences.h: new constants for tool und menu bar style sheets which only affect tool and menu bar and not the items therein * graphics/Figure.cc: include gui-preferences.h; (Figure): set style sheet for menu bar with reduced vertical spacing * graphics/ToolBar.cc: include gui-preferences.h; (ToolBar): set style sheet for tool bar with reduced vertical spacing * main-window.cc (construct_tool_bar): use style sheet string for tool bar which was defined in gui-preferences.h * octave-dock-widget.cc (handle_settings): newline for readability * history-dock-widget.cc (construct): reduce spacing in the used layout * workspace-view.cc (workspace_view): reduce spacing in the used layout

--- a/libgui/src/main-window.cc	Sat Oct 05 14:04:36 2019 -0700
+++ b/libgui/src/main-window.cc	Sun Oct 06 22:25:36 2019 +0200
@@ -2631,9 +2631,7 @@
   {
     m_main_tool_bar = addToolBar (tr ("Toolbar"));
     m_main_tool_bar->setStyleSheet (m_main_tool_bar->styleSheet ()
-             + QString ("margin-top: 1px; margin-bottom: 1px;"
-                        "margin-left: 3px; margin-right: 3px;"
-                        "border: 0px;"));
+                                    + octgui_toolbar_style);
 
     m_main_tool_bar->setObjectName ("MainToolBar");
     m_main_tool_bar->addAction (m_new_script_action);