Move sub-namespace typedefs to typedefs.js

Here too there is one problem case.

src/ol/source/imagesource.js

@@ -11,17 +11,6 @@ goog.require('ol.reproj.Image');
 goog.require('ol.source.Source');
 
 
-/**
- * @typedef {{attributions: (ol.AttributionLike|undefined),
- *            extent: (null|ol.Extent|undefined),
- *            logo: (string|olx.LogoOptions|undefined),
- *            projection: ol.proj.ProjectionLike,
- *            resolutions: (Array.<number>|undefined),
- *            state: (ol.source.State|undefined)}}
- */
-ol.source.ImageOptions;
-
-
 /**
  * @classdesc
  * Abstract base class; normally only used for creating subclasses and not