Fix windows margin scaling bug

components/printing/renderer/print_web_view_helper.cc

 // 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.
 
 #include "components/printing/renderer/print_web_view_helper.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1835 matching lines @@
   ComputePageLayoutInPointsForCss(frame, params.page_number, params.params,
                                   ignore_css_margins_, &css_scale_factor,
                                   &page_layout_in_points);
   gfx::Size page_size;
   gfx::Rect content_area;
   GetPageSizeAndContentAreaFromPageLayout(page_layout_in_points, &page_size,
                                           &content_area);
   int dpi = static_cast<int>(params.params.dpi);
   // Calculate the actual page size and content area in dpi.
   if (page_size_in_dpi) {
+    // Windows uses this for the actual page size. We have scaled page size
+    // to get blink to reflow the page, so scale it back to the real size
+    // before returning it.
     *page_size_in_dpi =
         gfx::Size(static_cast<int>(ConvertUnitDouble(page_size.width(),
-                                                     kPointsPerInch, dpi)),
+                                                     kPointsPerInch, dpi) *
+                                   css_scale_factor),
                   static_cast<int>(ConvertUnitDouble(page_size.height(),
-                                                     kPointsPerInch, dpi)));
+                                                     kPointsPerInch, dpi) *
+                                   css_scale_factor));
   }
 
   if (content_area_in_dpi) {
     // Output PDF matches paper size and should be printer edge to edge.
     *content_area_in_dpi =
         gfx::Rect(0, 0, page_size_in_dpi->width(), page_size_in_dpi->height());
   }
 
   gfx::Rect canvas_area =
       params.params.display_header_footer ? gfx::Rect(page_size) : content_area;
@@ skipping 478 matching lines @@
       blink::WebConsoleMessage::LevelWarning, message));
   return false;
 }
 
 void PrintWebViewHelper::ScriptingThrottler::Reset() {
   // Reset counter on successful print.
   count_ = 0;
 }
 
 }  // namespace printing