Use DPI from Print Preview on Windows, handle non square

chrome/browser/resources/print_preview/native_layer.js

Index: chrome/browser/resources/print_preview/native_layer.js
diff --git a/chrome/browser/resources/print_preview/native_layer.js b/chrome/browser/resources/print_preview/native_layer.js
index 6b522fe1988cb55c253e89a8d4295276c51f0eac..652c87cc8799b9cd0bd1c109d909364d267e44d0 100644
--- a/chrome/browser/resources/print_preview/native_layer.js
+++ b/chrome/browser/resources/print_preview/native_layer.js
@@ -312,6 +312,10 @@ cr.define('print_preview', function() {
         'copies': 1,
         'collate': true,
         'rasterizePDF': false,
+        'dpiHorizontal': "horizontal_dpi" in printTicketStore.dpi.getValue() ?
+           printTicketStore.dpi.getValue().horizontal_dpi : 0,
+        'dpiVertical': "vertical_dpi" in printTicketStore.dpi.getValue() ?
+           printTicketStore.dpi.getValue().vertical_dpi : 0,
         'shouldPrintBackgrounds': printTicketStore.cssBackground.getValue(),
         'shouldPrintSelectionOnly': printTicketStore.selectionOnly.getValue()
       };
@@ -387,6 +391,10 @@ cr.define('print_preview', function() {
         'printWithExtension': destination.isExtension,
         'rasterizePDF': printTicketStore.rasterize.getValue(),
         'scaleFactor': printTicketStore.scaling.getValueAsNumber(),
+        'dpiHorizontal': "horizontal_dpi" in printTicketStore.dpi.getValue() ?
+           printTicketStore.dpi.getValue().horizontal_dpi : 0,
+        'dpiVertical': "vertical_dpi" in printTicketStore.dpi.getValue() ?
+           printTicketStore.dpi.getValue().vertical_dpi : 0,
         'deviceName': destination.id,
         'isFirstRequest': false,
         'requestID': -1,