PrintPreview:[MAC & WIN] Added code to show the native printer management dialog.

chrome/browser/printing/printer_manager_dialog_win.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/printing/printer_manager_dialog.h"
+
+#include <windows.h>
+#include <shellapi.h>
+
+#include "base/file_util.h"

[Lei Zhang, 2011/04/28 01:14:12]

nit: you only need file_path.h.

[kmadhusu, 2011/04/28 15:44:21]

Done.

+#include "base/path_service.h"
+#include "base/threading/thread.h"
+#include "chrome/browser/browser_process.h"
+
+namespace printing {
+
+// A helper method that opens the printer management dialog.
+class OpenPrintersDialogTask : public Task {
+ public:
+  OpenPrintersDialogTask() {}
+
+  virtual void Run() {
+    FilePath rundll32;
+    PathService::Get(base::DIR_SYSTEM, &rundll32);
+    rundll32 = rundll32.AppendASCII("rundll32.exe");
+
+    FilePath shell32dll;
+    PathService::Get(base::DIR_SYSTEM, &shell32dll);

[Lei Zhang, 2011/04/28 01:14:12]

only need to call PathService::Get() once:

FilePath sys_dir;
PathService::Get(base::DIR_SYSTEM, &sys_dir);
FilePath rundll32 = sys_dir.AppendASCII("rundll32.exe");
FilePath shell32dll = sys_dir.AppendASCII("shell32.dll");

[kmadhusu, 2011/04/28 15:44:21]

Done.

+    shell32dll = shell32dll.AppendASCII("shell32.dll");
+
+    std::wstring args(shell32dll.value());
+    args.append(L",SHHelpShortcuts_RunDLL PrintersFolder");
+    ShellExecute(NULL, L"open", rundll32.value().c_str(), args.c_str(), NULL,
+                 SW_SHOWNORMAL);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(OpenPrintersDialogTask);
+};
+
+void PrinterManagerDialog::ShowPrinterManagerDialog() {
+  base::Thread* thread = g_browser_process->file_thread();
+  DCHECK(thread);

[Lei Zhang, 2011/04/28 01:14:12]

nit: you don't need this DCHECK. If |thread| is null, You'll crash immediately
afterwards anyway. You can just call
g_browser_process->file_thread()->message_loop()...

[kmadhusu, 2011/04/28 15:44:21]

Done.

+  thread->message_loop()->PostTask(FROM_HERE, new OpenPrintersDialogTask);
+}
+
+}  // namespace printing