| text | The text associated with the GUIContent.text. |
| icon | The icon associated with the GUIContent.image. |
| iconName | The name of the icon. |
| tooltip | The tooltip to display when the cursor hovers over the icon. |
| messageType | The type of the message to fetch the icon for. |
Gets the GUIContent from Unity built-in resources with the given information or creates a GUIContent for a GUI element.
The text and the tooltip are localized and loaded with an icon.
Typically, the icon from `Assets/Editor Default Resources/Icons` is fetched using the icon name. Only the name of the icon, without the .png extension is needed.
If a message type is specified instead of an icon or an icon name, the GUIContent.image is the icon associated with that message type.