Fixed a crash with some HP printer drivers (when invoking PTGetPrintCapabilit...

printing/backend/win_helper.h

 // Copyright (c) 2010 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 PRINTING_BACKEND_WIN_HELPER_H_
 #define PRINTING_BACKEND_WIN_HELPER_H_
 #pragma once
 
 #include <objidl.h>
 #include <winspool.h>
@@ skipping 40 matching lines @@
                                              EPrintTicketScope scope,
                                              IStream* result_ticket,
                                              BSTR* error_message);
   static HRESULT ReleaseMemory(PVOID buffer);
   static HRESULT CloseProvider(HPTPROVIDER provider);
  private:
   XPSModule() { }
   static bool InitImpl();
 };
 
+// See comments in cc file explaining why we need this.
+class ScopedXPSInitializer {
+ public:
+  ScopedXPSInitializer();
+  ~ScopedXPSInitializer();
+
+  bool initialized() const { return initialized_; }
+
+ private:
+  bool initialized_;
+};
+
 }  // namespace printing
 
 #endif  // PRINTING_BACKEND_WIN_HELPER_H_