[Print Preview] Re-add flags for register promos

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 <string>
 
@@ skipping 1341 matching lines @@
 
 #endif
 
 
 #if defined(ENABLE_MDNS)
 void PrintPreviewHandler::LocalPrinterChanged(
     bool added,
     const std::string& name,
     bool has_local_printing,
     const local_discovery::DeviceDescription& description) {
-  base::DictionaryValue info;
-  FillPrinterDescription(name, description, has_local_printing, &info);
-  web_ui()->CallJavascriptFunction("onPrivetPrinterChanged", info);
+  CommandLine* command_line = CommandLine::ForCurrentProcess();
+  if (has_local_printing ||
+      command_line->HasSwitch(switches::kEnablePrintPreviewRegisterPromos)) {
+    base::DictionaryValue info;
+    FillPrinterDescription(name, description, has_local_printing, &info);
+    web_ui()->CallJavascriptFunction("onPrivetPrinterChanged", info);
+  }
 }
 
 void PrintPreviewHandler::LocalPrinterRemoved(const std::string& name) {
 }
 
 void PrintPreviewHandler::LocalPrinterCacheFlushed() {
 }
 
 void PrintPreviewHandler::PrivetCapabilitiesUpdateClient(
     scoped_ptr<local_discovery::PrivetHTTPClient> http_client) {
@@ skipping 149 matching lines @@
     int http_code) {
   base::FundamentalValue http_code_value(http_code);
   web_ui()->CallJavascriptFunction("onPrivetPrintFailed", http_code_value);
 }
 
 void PrintPreviewHandler::FillPrinterDescription(
     const std::string& name,
     const local_discovery::DeviceDescription& description,
     bool has_local_printing,
     base::DictionaryValue* printer_value) {
+  CommandLine* command_line = CommandLine::ForCurrentProcess();
+
   printer_value->SetString("serviceName", name);
   printer_value->SetString("name", description.name);
   printer_value->SetBoolean("hasLocalPrinting", has_local_printing);
   printer_value->SetBoolean(
       "isUnregistered",
-      description.id.empty());
+      description.id.empty() &&
+      command_line->HasSwitch(switches::kEnablePrintPreviewRegisterPromos));
   printer_value->SetString("cloudID", description.id);
 }
 
 #endif