Print Preview: Make useCloudPrint a WebUI event

chrome/browser/ui/webui/print_preview/print_preview_handler.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/webui/print_preview/print_preview_handler.h"
 
 #include <ctype.h>
 #include <stddef.h>
 
 #include <map>
@@ skipping 1419 matching lines @@
 
 void PrintPreviewHandler::SendCloudPrintEnabled() {
   Profile* profile = Profile::FromBrowserContext(
       preview_web_contents()->GetBrowserContext());
   PrefService* prefs = profile->GetPrefs();
   if (prefs->GetBoolean(prefs::kCloudPrintSubmitEnabled)) {
     base::DictionaryValue settings;
     settings.SetString(kCloudPrintUrl,
                        GURL(cloud_devices::GetCloudPrintURL()).spec());
     settings.SetBoolean(kAppKioskMode, chrome::IsRunningInForcedAppMode());
-    web_ui()->CallJavascriptFunctionUnsafe("setUseCloudPrint", settings);
+    FireWebUIListener("use-cloud-print", settings);

[dpapad, 2017/06/27 18:54:07]

Do we need to package the string and the boolean to a single object anymore?
FireWebUIListener() supports multiple arguments.

[rbpotter, 2017/06/27 22:30:29]

Done.

   }
 }
 
 void PrintPreviewHandler::SendCloudPrintJob(const std::string& callback_id,
                                             const base::RefCountedBytes* data) {
   // BASE64 encode the job data.
   const base::StringPiece raw_data(reinterpret_cast<const char*>(data->front()),
                                    data->size());
   std::string base64_data;
   base::Base64Encode(raw_data, &base64_data);
@@ skipping 447 matching lines @@
 
 void PrintPreviewHandler::UnregisterForGaiaCookieChanges() {
   if (gaia_cookie_manager_service_)
     gaia_cookie_manager_service_->RemoveObserver(this);
 }
 
 void PrintPreviewHandler::SetPdfSavedClosureForTesting(
     const base::Closure& closure) {
   pdf_file_saved_closure_ = closure;
 }