Bug 298835 Merge e4 Project Path Variable back into the 3.6 stream
The virtual folder and filters changes are already in 3.6, the project path variable changes in e4 still remains to be merged.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/PathVariablesGroup.java
button.setLayoutData(data);
        return data;
    }
    /**
     * Sets the enabled state of the group's widgets.
     * Does nothing if called prior to calling <code>createContents</code>.
     * 
     * @param enabled the new enabled state of the group's widgets
     */
    public void setEnabled(boolean enabled) {
        if (variableTable != null && !variableTable.isDisposed()) {
            variableLabel.setEnabled(enabled);
            variableTable.setEnabled(enabled);
            addButton.setEnabled(enabled);
            if (enabled) {
				updateEnabledState();
			} else {
                editButton.setEnabled(enabled);
                removeButton.setEnabled(enabled);
            }
        }
    }
    /**
     * Updates the widget's current state: refreshes the table with the current 
     * defined variables, selects the item corresponding to the given variable 
     * (selects the first item if <code>null</code> is provided) and updates 
     * the enabled state for the Add/Remove/Edit buttons.
     * 
     * @param selectedVarName the name of the variable to be selected (may be null)
     */