Revert of More System Dialog printing code disabled on Windows.

chrome/browser/ui/webui/print_preview/print_preview_handler.cc

Index: chrome/browser/ui/webui/print_preview/print_preview_handler.cc
diff --git a/chrome/browser/ui/webui/print_preview/print_preview_handler.cc b/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
index 577c4554ea8ea9b7d8bd04335ce3353a3d3b64ea..3ad23457860064a6a14e87de2b276f9097708d5b 100644
--- a/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
+++ b/chrome/browser/ui/webui/print_preview/print_preview_handler.cc
@@ -566,11 +566,9 @@ void PrintPreviewHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback("getPrinterCapabilities",
       base::Bind(&PrintPreviewHandler::HandleGetPrinterCapabilities,
                  base::Unretained(this)));
-#if !defined(OS_WIN)
   web_ui()->RegisterMessageCallback("showSystemDialog",
       base::Bind(&PrintPreviewHandler::HandleShowSystemDialog,
                  base::Unretained(this)));
-#endif  // !OS_WIN
   web_ui()->RegisterMessageCallback("signIn",
       base::Bind(&PrintPreviewHandler::HandleSignin,
                  base::Unretained(this)));
@@ -1024,7 +1022,6 @@ void PrintPreviewHandler::HandleManageCloudPrint(
       false));
 }
 
-#if !defined(OS_WIN)
 void PrintPreviewHandler::HandleShowSystemDialog(
     const base::ListValue* /*args*/) {
   ReportStats();
@@ -1044,7 +1041,6 @@ void PrintPreviewHandler::HandleShowSystemDialog(
       static_cast<PrintPreviewUI*>(web_ui()->GetController());
   print_preview_ui->OnCancelPendingPreviewRequest();
 }
-#endif  // !OS_WIN
 
 void PrintPreviewHandler::HandleManagePrinters(
     const base::ListValue* /*args*/) {
@@ -1290,11 +1286,9 @@ void PrintPreviewHandler::OnPrintPreviewFailed() {
   ReportUserActionHistogram(PREVIEW_FAILED);
 }
 
-#if !defined(OS_WIN)
 void PrintPreviewHandler::ShowSystemDialog() {
   HandleShowSystemDialog(NULL);
 }
-#endif  // !OS_WIN
 
 void PrintPreviewHandler::FileSelected(const base::FilePath& path,
                                        int index, void* params) {