List printers managed by extensions in print preview

extensions/browser/api/printer_provider_internal/printer_provider_internal_api.h

 // Copyright 2015 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.
 
 #ifndef EXTENSIONS_BROWSER_API_PRINTER_PROVIDER_INTERNAL_PRINTER_PROVIDER_INTERNAL_API_H_
 #define EXTENSIONS_BROWSER_API_PRINTER_PROVIDER_INTERNAL_PRINTER_PROVIDER_INTERNAL_API_H_
 
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "extensions/browser/api/printer_provider_internal/printer_provider_internal_api_observer.h"
@@ skipping 31 matching lines @@
 
  private:
   friend class BrowserContextKeyedAPIFactory<PrinterProviderInternalAPI>;
   friend class PrinterProviderInternalReportPrintersFunction;
   friend class PrinterProviderInternalReportPrinterCapabilityFunction;
   friend class PrinterProviderInternalReportPrintResultFunction;
 
   // Notifies observers that a printerProvider.onGetPrintersRequested callback
   // has been called. Called from
   // |PrinterProviderInternalReportPrintersFunction|.
-  void NotifyGetPrintersResult(const Extension* extension,
-                               int request_id,
-                               const base::ListValue& printers);
+  void NotifyGetPrintersResult(
+      const Extension* extension,
+      int request_id,
+      const PrinterProviderInternalAPIObserver::PrinterInfoVector& printers);
 
   // Notifies observers that a printerProvider.onGetCapabilityRequested callback
   // has been called. Called from
   // |PrinterProviderInternalReportPrinterCapabilityFunction|.
   void NotifyGetCapabilityResult(const Extension* extension,
                                  int request_id,
                                  const base::DictionaryValue& capability);
 
   // Notifies observers that a printerProvider.onPrintRequested callback has
   // been called. Called from
@@ skipping 57 matching lines @@
  private:
   DECLARE_EXTENSION_FUNCTION("printerProviderInternal.reportPrinters",
                              PRINTERPROVIDERINTERNAL_REPORTPRINTERS)
 
   DISALLOW_COPY_AND_ASSIGN(PrinterProviderInternalReportPrintersFunction);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_API_PRINTER_PROVIDER_INTERNAL_PRINTER_PROVIDER_INTERNAL_API_H_