Allow the PDF extension for chrome://print pages.

content/public/browser/web_ui_data_source.h

 // Copyright (c) 2013 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 CONTENT_PUBLIC_BROWSER_WEB_UI_DATA_SOURCE_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_UI_DATA_SOURCE_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
@@ skipping 69 matching lines @@
   virtual void SetRequestFilter(const HandleRequestCallback& callback) = 0;
 
   // The following map to methods on URLDataSource. See the documentation there.
   // NOTE: it's not acceptable to call DisableContentSecurityPolicy for new
   // pages, see URLDataSource::ShouldAddContentSecurityPolicy and talk to
   // tsepez.
 
   // Currently only used by embedders for WebUIs with multiple instances.
   virtual void DisableReplaceExistingSource() = 0;
   virtual void DisableContentSecurityPolicy() = 0;
+  virtual void OverrideContentSecurityPolicyScriptSrc(
+      const std::string& data) = 0;
   virtual void OverrideContentSecurityPolicyObjectSrc(
       const std::string& data) = 0;
   virtual void OverrideContentSecurityPolicyChildSrc(
       const std::string& data) = 0;
   virtual void DisableDenyXFrameOptions() = 0;
 
   // Tells the loading code that resources are gzipped on disk. TODO(dbeam):
   // write a streaming $i18n{} replacer and remove the "DisableI18n" part.
   virtual void DisableI18nAndUseGzipForAllPaths() = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_UI_DATA_SOURCE_H_