Restored disable print preview policy.

chrome/renderer/printing/print_web_view_helper.cc

Index: chrome/renderer/printing/print_web_view_helper.cc
diff --git a/chrome/renderer/printing/print_web_view_helper.cc b/chrome/renderer/printing/print_web_view_helper.cc
index 53a66ee29263edee54837201297c2b99c9ba9d9c..05247b11d5c6cc17af3fd5b5bce02bed76bd11d1 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -784,6 +784,10 @@ PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
       is_loading_(false),
       is_scripted_preview_delayed_(false),
       weak_ptr_factory_(this) {
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDisablePrintPreview)) {
+    DisablePreview();
+  }
 }
 
 PrintWebViewHelper::~PrintWebViewHelper() {}