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..c079159380856c2318f7b0b27e8db0e219664f06 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -67,12 +67,6 @@ const char kPageLoadScriptFormat[] =
 
 const char kPageSetupScriptFormat[] = "setup(%s);";
 
-#if defined(ENABLE_FULL_PRINTING)
-bool g_is_preview_enabled_ = true;
-#else
-bool g_is_preview_enabled_ = false;
-#endif
-
 void ExecuteScript(blink::WebFrame* frame,
                    const char* script_format,
                    const base::Value& parameters) {
@@ -405,6 +399,15 @@ PrintMsg_Print_Params CalculatePrintParamsForCss(
   return result_params;
 }
 
+bool IsPrintPreviewEnabled() {
+#if defined(ENABLE_FULL_PRINTING)
+  return !CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kDisablePrintPreview);
+#else
+  return false;
+#endif
+}
+
 }  // namespace
 
 FrameReference::FrameReference(blink::WebLocalFrame* frame) {
@@ -775,6 +778,7 @@ PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
     : content::RenderViewObserver(render_view),
       content::RenderViewObserverTracker<PrintWebViewHelper>(render_view),
       reset_prep_frame_view_(false),
+      is_preview_enabled_(IsPrintPreviewEnabled()),
       is_print_ready_metafile_sent_(false),
       ignore_css_margins_(false),
       is_scripted_printing_blocked_(false),
@@ -788,11 +792,6 @@ PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
 
 PrintWebViewHelper::~PrintWebViewHelper() {}
 
-// static
-void PrintWebViewHelper::DisablePreview() {
-  g_is_preview_enabled_ = false;
-}
-
 bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
     blink::WebFrame* frame, bool user_initiated) {
 #if defined(OS_ANDROID)
@@ -803,7 +802,7 @@ bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
   // is app modal). If the print was initiated through user action, don't
   // throttle. Or, if the command line flag to skip throttling has been set.
   return !is_scripted_printing_blocked_ &&
-         (user_initiated || g_is_preview_enabled_ ||
+         (user_initiated || is_preview_enabled_ ||
           scripting_throttler_.IsAllowed(frame));
 }
 
@@ -834,7 +833,7 @@ void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
   if (!IsScriptInitiatedPrintAllowed(frame, user_initiated))
     return;
 
-  if (!g_is_preview_enabled_) {
+  if (!is_preview_enabled_) {
     Print(frame, blink::WebNode());
   } else {
     print_preview_context_.InitWithFrame(frame);
@@ -862,6 +861,7 @@ bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
 
 void PrintWebViewHelper::OnPrintForPrintPreview(
     const base::DictionaryValue& job_settings) {
+  DCHECK(is_preview_enabled_);
   // If still not finished with earlier print request simply ignore.
   if (prep_frame_view_)
     return;
@@ -996,6 +996,7 @@ bool PrintWebViewHelper::IsPrintToPdfRequested(
 }
 
 void PrintWebViewHelper::OnPrintPreview(const base::DictionaryValue& settings) {
+  DCHECK(is_preview_enabled_);
   print_preview_context_.OnPrintPreview();
 
   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
@@ -1198,6 +1199,7 @@ void PrintWebViewHelper::SetScriptedPrintBlocked(bool blocked) {
 }
 
 void PrintWebViewHelper::OnInitiatePrintPreview(bool selection_only) {
+  DCHECK(is_preview_enabled_);
   blink::WebLocalFrame* frame = NULL;
   GetPrintFrame(&frame);
   DCHECK(frame);
@@ -1231,7 +1233,7 @@ void PrintWebViewHelper::PrintNode(const blink::WebNode& node) {
 
   // Make a copy of the node, in case RenderView::OnContextMenuClosed resets
   // its |context_menu_node_|.
-  if (!g_is_preview_enabled_) {
+  if (!is_preview_enabled_) {
     blink::WebNode duplicate_node(node);
     Print(duplicate_node.document().frame(), duplicate_node);
   } else {
@@ -1294,6 +1296,7 @@ void PrintWebViewHelper::DidFinishPrinting(PrintingResult result) {
       break;
 
     case FAIL_PREVIEW:
+      DCHECK(is_preview_enabled_);
       int cookie = print_pages_params_ ?
           print_pages_params_->params.document_cookie : 0;
       if (notify_browser_of_print_failure_) {
@@ -1459,6 +1462,7 @@ bool PrintWebViewHelper::UpdatePrintSettings(
     blink::WebLocalFrame* frame,
     const blink::WebNode& node,
     const base::DictionaryValue& passed_job_settings) {
+  DCHECK(is_preview_enabled_);
   const base::DictionaryValue* job_settings = &passed_job_settings;
   base::DictionaryValue modified_job_settings;
   if (job_settings->empty()) {