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

chrome/renderer/print_web_view_helper.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 CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #define CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 142 matching lines @@
       const printing::PageSizeMargins& page_layout_in_points,
       gfx::Size* page_size,
       gfx::Rect* content_area);
 
   // Update |ignore_css_margins_| based on settings.
   void UpdateFrameMarginsCssInfo(const base::DictionaryValue& settings);
 
   // Returns true if the current destination printer is PRINT_TO_PDF.
   bool IsPrintToPdfRequested(const base::DictionaryValue& settings);
 
+  // Returns false if
+  // (1) The current destination printer is SAVE_AS_PDF or
+  // (2) Source is PDF. This is the first preview request and print scaling
+  // option is disabled for initiator renderer plugin.
+  // (3) Source is PDF and the user has requested not to fit to printable area
+  // via |job_settings|.
+  // In all other cases returns true to fit the print contents in paper size.
+  bool IsFitToPaperSizeRequested(bool source_is_html,
+                                 const base::DictionaryValue& job_settings,
+                                 const PrintMsg_Print_Params& params);
+
   // Initiate print preview.
   void OnInitiatePrintPreview();
 
   // Start the process of generating a print preview using |settings|.
   void OnPrintPreview(const base::DictionaryValue& settings);
 
   // Initialize the print preview document.
   bool CreatePreviewDocument();
 
   // Renders a print preview page. |page_number| is 0-based.
@@ skipping 294 matching lines @@
     enum PrintPreviewErrorBuckets error_;
 
     State state_;
   };
 
   PrintPreviewContext print_preview_context_;
   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 };
 
 #endif  // CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_