Export a function from the PDF plugin to get the dimensions of a PDF page.

pdf/pdf_engine.h

 // 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.
 
 #ifndef PDF_PDF_ENGINE_H_
 #define PDF_PDF_ENGINE_H_
 
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
@@ skipping 294 matching lines @@
   // See the definition of RenderPDFPageToBitmap in pdf.cc for details.
   virtual bool RenderPDFPageToBitmap(const void* pdf_buffer,
                                      int pdf_buffer_size,
                                      int page_number,
                                      const RenderingSettings& settings,
                                      void* bitmap_buffer) = 0;
   virtual bool GetPDFDocInfo(const void* pdf_buffer,
                              int buffer_size,
                              int* page_count,
                              double* max_page_width) = 0;
+
+  virtual bool GetPDFPageSizeByIndex(const void* pdf_buffer,
+                                     int buffer_size, int index,
+                                     double* width, double* height) = 0;
 };
 
 }  // namespace chrome_pdf
 
 #endif  // PDF_PDF_ENGINE_H_