Resize the zoom box width to fit the content - fix embedding - address comments

web/viewer.css

@@ -667,6 +667,7 @@ html[dir='rtl'] .dropdownToolbarButton {
 }
 
 .dropdownToolbarButton {
+  width: 120px;
   max-width: 120px;
   padding: 3px 2px 2px;
   overflow: hidden;

web/viewer.js

@@ -3153,14 +3153,16 @@ window.addEventListener('localized', function localized(evt) {
   document.getElementsByTagName('html')[0].dir = mozL10n.getDirection();
 
   // Adjust the width of the zoom box to fit the content.
+  PDFView.animationStartedPromise.then(
+    function() {
       var container = document.getElementById('scaleSelectContainer');
       var select = document.getElementById('scaleSelect');
-
       select.setAttribute('style', 'min-width: inherit;');
       var width = select.clientWidth + 8;
+      select.setAttribute('style', 'min-width: ' + (width + 20) + 'px;');
       container.setAttribute('style', 'min-width: ' + width + 'px; ' +
                                       'max-width: ' + width + 'px;');
-  select.setAttribute('style', 'min-width: ' + (width + 20) + 'px;');
+  });
 }, true);
 
 window.addEventListener('scalechange', function scalechange(evt) {