PrintPreview: Added code to identify the printer default duplex value.

chrome/renderer/mock_render_thread.cc

Index: chrome/renderer/mock_render_thread.cc
diff --git a/chrome/renderer/mock_render_thread.cc b/chrome/renderer/mock_render_thread.cc
index c6fc5192aae160d05e167b620e5625a3f6c43d2e..213215ca699e15d8fdd5ac45c4f36d2b07d4b01f 100644
--- a/chrome/renderer/mock_render_thread.cc
+++ b/chrome/renderer/mock_render_thread.cc
@@ -242,10 +242,10 @@ void MockRenderThread::OnUpdatePrintSettings(
   if (!job_settings.GetBoolean(printing::kSettingLandscape, NULL) ||
       !job_settings.GetBoolean(printing::kSettingCollate, NULL) ||
       !job_settings.GetBoolean(printing::kSettingColor, NULL) ||
+      !job_settings.GetDictionary(printing::kSettingDuplexModeInfo, NULL) ||
       !job_settings.GetBoolean(printing::kSettingPrintToPDF, NULL) ||
       !job_settings.GetBoolean(printing::kIsFirstRequest, NULL) ||
       !job_settings.GetString(printing::kSettingDeviceName, &dummy_string) ||
-      !job_settings.GetInteger(printing::kSettingDuplexMode, NULL) ||
       !job_settings.GetInteger(printing::kSettingCopies, NULL) ||
       !job_settings.GetString(printing::kPreviewUIAddr, &dummy_string) ||
       !job_settings.GetInteger(printing::kPreviewRequestID, NULL)) {