Editors: Move id() from editor to document.

Change-Id: Ib81076842ab1c16832224790194b001206404d64
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/imageviewer/imageviewer.cpp

@@ -62,8 +62,6 @@ ImageViewer::ImageViewer(QWidget *parent)
     : IEditor(parent),
     d(new ImageViewerPrivate)
 {
-    setId(Constants::IMAGEVIEWER_ID);
-
     d->file = new ImageViewerFile(this);
     d->imageView = new ImageView();