Bug 157985 [Workbench] Add 'Hide toolbar' action to context menu
M2 The 'Hide toolbar' action should be added to the context menu on toolbars. That's where I first looked for it.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/WorkbenchActionBuilder.java
menu.add(closeAllPerspsAction);
    }
    /**
     * Adds the keyboard navigation submenu to the specified menu.
     */
    private void addWorkingSetBuildActions(MenuManager menu) {
        buildWorkingSetMenu = new MenuManager(IDEWorkbenchMessages.Workbench_buildSet);
        IContributionItem workingSetBuilds = new BuildSetMenu(window,
                getActionBarConfigurer());
        buildWorkingSetMenu.add(workingSetBuilds);
        menu.add(buildWorkingSetMenu);
    }
    /**
     * Adds the keyboard navigation submenu to the specified menu.
     */
    private void addKeyboardShortcuts(MenuManager menu) {
        MenuManager subMenu = new MenuManager(IDEWorkbenchMessages.Workbench_shortcuts, "shortcuts"); 
        menu.add(subMenu);
        subMenu.add(showPartPaneMenuAction);
        subMenu.add(showViewMenuAction);
        subMenu.add(new Separator());
        subMenu.add(maximizePartAction);
        subMenu.add(minimizePartAction);
        subMenu.add(new Separator());
        subMenu.add(activateEditorAction);
        subMenu.add(nextEditorAction);
        subMenu.add(prevEditorAction);
        subMenu.add(switchToEditorAction);
        subMenu.add(openEditorDropDownAction);
        subMenu.add(new Separator());