TinyMCE: prevent showing the placeholder URL when adding a link and clicking more than once on the Insert Link button.

Props iseulde.
Fixes #36637 for trunk.

git-svn-id: https://develop.svn.wordpress.org/trunk@37301 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/js/tinymce/plugins/wplink/plugin.js

@@ -488,7 +488,7 @@
 				edit = $linkNode.attr( 'data-wplink-edit' );
 
 				if ( href === '_wp_link_placeholder' || edit ) {
-					if ( edit && ! inputInstance.getURL() ) {
+					if ( href !== '_wp_link_placeholder' && ! inputInstance.getURL() ) {
 						inputInstance.setURL( href );
 					}