Merge pull request #3180 from edx/christina/iframe_binding_bug

Check iframe src for the specific value TinyMCE uses.

cms/static/js/spec/utils/handle_iframe_binding_spec.js

@@ -12,6 +12,15 @@ function ($, _, IframeBinding) {
         iframe_html += '<embed type="application/x-shockwave-flash" src="http://www.youtube.com/embed/NHd27UvY-lw" height="315" width="560">';
         doc.body.innerHTML = iframe_html;
 
+        var verify_no_modification = function (src) {
+            iframe_html = '<iframe width="618" height="350" src="' + src + '" frameborder="0" allowfullscreen></iframe>';
+            doc.body.innerHTML = iframe_html;
+
+            IframeBinding.iframeBinding(doc);
+
+            expect($(doc).find("iframe")[0].src).toEqual(src);
+        };
+
         it("modifies src url of DOM iframe and embed elements when iframeBinding function is executed", function () {
             expect($(doc).find("iframe")[0].src).toEqual("http://www.youtube.com/embed/NHd27UvY-lw");
             expect($(doc).find("iframe")[1].src).toEqual("http://www.youtube.com/embed/NHd27UvY-lw?allowFullScreen=false");
@@ -35,12 +44,11 @@ function ($, _, IframeBinding) {
         });
 
         it("does not modify src url of DOM iframe if it is empty", function () {
-            iframe_html = '<iframe width="618" height="350" src="" frameborder="0" allowfullscreen></iframe>';
-            doc.body.innerHTML = iframe_html;
-
-            IframeBinding.iframeBinding(doc);
+            verify_no_modification("");
+        });
 
-            expect($(doc).find("iframe")[0].src).toEqual("");
+        it("does nothing on tinymce iframe", function () {
+            verify_no_modification("javascript:");
         });
     });
 });

cms/static/js/utils/handle_iframe_binding.js

@@ -29,7 +29,10 @@ define(["jquery"], function($) {
                             $(this).attr('src', newString + '?' + wmode + '&' + oldString);
                         }
                     }
-                    else {
+                    // The TinyMCE editor is hosted in an iframe, and before the iframe is
+                    // removed we execute this code. To avoid throwing an error when setting the
+                    // attr, check that the source doesn't start with the value specified by TinyMCE ('javascript:""').
+                    else if (ifr_source.lastIndexOf("javascript:", 0) !== 0) {
                         $(this).attr('src', ifr_source + '?' + wmode);
                     }
                 }