Reapplies all the IPC system work (reverts the revert r56272).

printing/pdf_ps_metafile_cairo.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_PDF_PS_METAFILE_CAIRO_H_
 #define PRINTING_PDF_PS_METAFILE_CAIRO_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 11 matching lines @@
 
 // This class uses Cairo graphics library to generate PostScript/PDF stream
 // and stores rendering results in a string buffer.
 class PdfPsMetafile {
  public:
   enum FileFormat {
     PDF,
     PS,
   };
 
+  PdfPsMetafile();
+
   // In the renderer process, callers should also call Init(void) to see if the
   // metafile can obtain all necessary rendering resources.
   // In the browser process, callers should also call Init(const void*, uint32)
   // to initialize the buffer |data_| to use SaveTo().
   explicit PdfPsMetafile(const FileFormat& format);
 
   ~PdfPsMetafile();
 
   // Initializes to a fresh new metafile. Returns true on success.
   // Note: Only call in the renderer to allocate rendering resources.
@@ skipping 71 matching lines @@
   std::string data_;
   // Buffer stores raw PDF/PS contents set by SetRawPageData.
   std::string raw_override_data_;
 
   DISALLOW_COPY_AND_ASSIGN(PdfPsMetafile);
 };
 
 }  // namespace printing
 
 #endif  // PRINTING_PDF_PS_METAFILE_CAIRO_H_