Restoring editor to the editable mode should respect command buttons state

[mdprw]

Steps to reproduce

1. Open any CKEditor full featured:

http://nightly.ckeditor.com/full/samples/

2. Disable templates command button:

CKEDITOR.instances.editor.commands.templates.disable();

3. Set editor to readOnly mode:

CKEDITOR.instances.editor.setReadOnly();

4. Set editor to editable mode:

CKEDITOR.instances.editor.setReadOnly(false);

Expected result

Previously disabled command buttons should mantain their state

Actual result

The command button is enabled

Other details (browser, OS, CKEditor version, installed plugins)

OS: Windows 7 Browser: Firefox 46.0.1 CKEditor: 4.5.9

[Jakub Ś]

You could always use ​http://docs.ckeditor.com/#!/api/CKEDITOR.editor-event-readOnly event to customize this behaviour, and this is implementer part to maintain custom parts here. In general it's preferred to automatically maintain command status with ​http://docs.ckeditor.com/#!/api/CKEDITOR.commandDefinition-property-readOnly

Please also note that some buttons are disabled before and after setting read-only. They handle their state managing CKEDITOR.TRISTATE_DISABLED and CKEDITOR.TRISTATE_OFF. Please check the indent, link (unlink) or clipboard plugins.