Bug 123496 [IDE] Use operation validation API for IDE actions
We should use the Resources/Core operation validation API in the IDE actions for manipulating resources.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/IDE.java
* is available.</li>
	 * </ol>
	 * </p>
	 * 
	 * @param file
	 *            the file
	 * @return an editor descriptor, appropriate for opening the file
	 * @throws PartInitException
	 *             if no editor can be found
	 */
    public static IEditorDescriptor getEditorDescriptor(IFile file)
            throws PartInitException {
		return getEditorDescriptor(file, true);
	}
    /**
	 * Returns an editor descriptor appropriate for opening the given file
	 * resource.
	 * <p>
	 * The editor descriptor is determined using a multistep process. This
	 * method will attempt to resolve the editor based on content-type bindings
	 * as well as traditional name/extension bindings if
	 * <code>determineContentType</code>is <code>true</code>.
	 * </p>
	 * <ol>
	 * <li>The file is consulted for a persistent property named
	 * <code>IDE.EDITOR_KEY</code> containing the preferred editor id to be
	 * used.</li>
	 * <li>The workbench editor registry is consulted to determine if an editor
	 * extension has been registered for the file type. If so, an instance of
	 * the editor extension is opened on the file. See