Add a `reset` method to `PDFFindbar`, and use it to clear parts of the find UI when the document is closed

web/pdf_find_bar.js

@@ -83,6 +83,10 @@ var PDFFindBar = (function PDFFindBarClosure() {
   }
 
   PDFFindBar.prototype = {
+    reset: function PDFFindBar_reset() {
+      this.updateUIState();
+    },
+
     dispatchEvent: function PDFFindBar_dispatchEvent(type, findPrev) {
       var event = document.createEvent('CustomEvent');
       event.initCustomEvent('find' + type, true, true, {

web/viewer.js

@@ -527,6 +527,7 @@ var PDFViewerApplication = {
     }
 
     this.findController.reset();
+    this.findBar.reset();
 
     if (typeof PDFBug !== 'undefined') {
       PDFBug.cleanup();