Bug 53386 [ActivityMgmt] Remove show All from everywhere except new wizards
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
protected void buttonPressed(int buttonId) {
		switch (buttonId) {
			case IDialogConstants.OK_ID :
				{
					okPressed();
					return;
				}
			case IDialogConstants.CANCEL_ID :
				{
					cancelPressed();
					return;
				}
			case IDialogConstants.HELP_ID :
				{
					helpPressed();
					return;
				}
		}
	}
	/* (non-Javadoc)
	 * @see org.eclipse.jface.dialogs.Dialog#cancelPressed()
	 */
	protected void cancelPressed() {
		
		Iterator nodes = preferenceManager.getElements(PreferenceManager.PRE_ORDER).iterator();
		while (nodes.hasNext()) {
			final IPreferenceNode node = (IPreferenceNode) nodes.next();
			if (node.getPage() != null) {
				Platform.run(new SafeRunnable() {
					public void run() {