Return additional info in WebPrintPresetOptions:

public/web/WebPrintPresetOptions.h

 // Copyright 2014 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 WebPrintPresetOptions_h
 #define WebPrintPresetOptions_h
 
 #include <vector>
 
 namespace blink {
@@ skipping 23 matching lines @@
     bool isScalingDisabled;
 
     // Specifies the number of copies to be printed.
     int copies;
 
     // Specifies duplex mode to be used for printing.
     WebDuplexMode duplexMode;
 
     // Specifies page range to be used for printing.
     WebPageRanges pageRanges;
+
+    // True if all the pages in the PDF are the same size.
+    bool isPageSizeUniform;
+
+    // Only valid if the page sizes are uniform. The page size in points.
+    WebSize uniformPageSize;
 };
 
 } // namespace blink
 
 #endif