Merge remote-tracking branch 'remotes/github/2.3-develop' into EPAM-PR-30

Author: VeronikaYarats

lib/web/mage/adminhtml/wysiwyg/tiny_mce/tinymce4Adapter.js

@@ -350,7 +350,7 @@ define([
          * @param {String} content
          */
         setContent: function (content) {
-            this.get(this.getId()).execCommand('mceSetContent', false, content);
+            this.get(this.getId()).setContent(content);
         },
 
         /**
@@ -559,10 +559,12 @@ define([
             var selection = editor.selection,
                 dom = editor.dom,
                 rng = dom.createRng(),
+                doc = editor.getDoc(),
                 markerHtml,
                 marker;
 
-            if (!selection.getContent().length) {
+            // Validate the range we're trying to fix is contained within the current editors document
+            if (!selection.getContent().length && jQuery.contains(doc, selection.getRng().startContainer)) {
                 markerHtml = '<span id="mce_marker" data-mce-type="bookmark">\uFEFF</span>';
                 selection.setContent(markerHtml);
                 marker = dom.get('mce_marker');