[FIX] portal, web_editor: responsive images but with inline display

Commit https://github.com/odoo/odoo/commit/abde8bddf8ec45cf12aab59e95c330321158cfba
made a small change to make all images responsive when they are added
with the editor. This had however the side effect of making them go to
a new line which may not be what we want.

addons/portal/static/src/less/portal.less

@@ -152,6 +152,10 @@ img, .media_iframe_video, .o_image {
         margin-right: @grid-gutter-width / 2;
     }
 }
+img {
+    // Make all images responsive by default but with inline-block display
+    .img-responsive(inline-block);
+}
 
 // Others
 ::-moz-selection {

addons/web_editor/static/src/js/widgets/widgets.js

@@ -286,7 +286,7 @@ var ImageWidget = MediaWidget.extend({
         var img = this.images[0];
         if (!img.isDocument) {
             if (!this.$media.is('img')) {
-                this._replaceMedia($('<img/>', {class: 'img img-responsive'}));
+                this._replaceMedia($('<img/>'));
             }
             this.$media.attr('src', img.src);
         } else {
@@ -409,7 +409,7 @@ var ImageWidget = MediaWidget.extend({
             var $div = $(el);
             if (/gif|jpe|jpg|png/.test($div.data('mimetype'))) {
                 var $img = $('<img/>', {
-                    class: 'img img-responsive',
+                    class: 'img-responsive',
                     src: $div.data('url') || $div.data('src'),
                 });
                 var def = $.Deferred();