gfx: Make conversions from Size to SizeF be explicit.

chrome/browser/ui/libgtk2ui/printing_gtk2_util.cc

 // 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.
 
 #include "chrome/browser/ui/libgtk2ui/printing_gtk2_util.h"
 
 #include <gtk/gtk.h>
 #include <gtk/gtkunixprint.h>
 
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "printing/print_settings.h"
 #include "printing/printing_context_linux.h"
 #include "printing/units.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gfx/geometry/size_f.h"
 
 namespace {
 
 const double kTopMarginInInch = 0.25;
 const double kBottomMarginInInch = 0.56;
 const double kLeftMarginInInch = 0.25;
 const double kRightMarginInInch = 0.25;
 
 }  // namespace
 
@@ skipping 63 matching lines @@
   // Thus this is only useful in print preview mode, where we manually set the
   // orientation and change the paper size ourselves.
   GtkPageOrientation orientation = gtk_print_settings_get_orientation(settings);
   // Set before SetPrinterPrintableArea to make it flip area if necessary.
   print_settings->SetOrientation(orientation == GTK_PAGE_ORIENTATION_LANDSCAPE);
   DCHECK_EQ(print_settings->device_units_per_inch(), dpi);
   print_settings->SetPrinterPrintableArea(physical_size_device_units,
                                           printable_area_device_units,
                                           true);
 }