[Print Preview]: Added code to support pdf fit to page functionality.

chrome/browser/ui/webui/print_preview/print_preview_ui.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_ui.h"
 
 #include <map>
 
 #include "base/lazy_instance.h"
 #include "base/memory/ref_counted_memory.h"
@@ skipping 311 matching lines @@
   ConstrainedHtmlUIDelegate* delegate = GetConstrainedDelegate();
   if (!delegate)
     return;
   delegate->GetHtmlDialogUIDelegate()->OnDialogClosed("");
   delegate->OnDialogCloseFromWebUI();
 }
 
 void PrintPreviewUI::OnReloadPrintersList() {
   web_ui()->CallJavascriptFunction("reloadPrintersList");
 }
+
+void PrintPreviewUI::OnPrintPreviewScalingDisabled() {
+  web_ui()->CallJavascriptFunction("printScalingDisabledForSourcePDF");
+}