Bug 125011 [Contributions] ActionContributionItem should use text for tooltip in toolitems
If an action is added to a toolbar, and it has a name, but no tooltip set, the name should be used as the tooltip (except when the text is actually displayed on the toolitem using setText()) Clients sometimes forget to set the tooltip text when no specific tooltip message exists.
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ActionContributionItem.java
if (enableStateChanged) {
                    boolean shouldBeEnabled = action.isEnabled()
                            && isEnabledAllowed();
                    if (ti.getEnabled() != shouldBeEnabled)
                        ti.setEnabled(shouldBeEnabled);
                }
                if (checkChanged) {
                    boolean bv = action.isChecked();
                    if (ti.getSelection() != bv)
                        ti.setSelection(bv);
                }
                return;
            }
            if (widget instanceof MenuItem) {
                MenuItem mi = (MenuItem) widget;
                if (textChanged) {
                    int accelerator = 0;
					String acceleratorText = null;
					IAction updatedAction = getAction();
					String text = null;
					accelerator = updatedAction.getAccelerator();
					ExternalActionManager.ICallback callback = ExternalActionManager
							.getInstance().getCallback();
					
					if ((accelerator != 0) && (callback != null)
                            && (callback.isAcceleratorInUse(accelerator))) {
                        accelerator = 0;
					}
					/*
					 * Process accelerators on GTK in a special way to avoid Bug