o Cleans up canonical extension_install_ui.cc to avoid #ifdefs when feasible....

chrome/browser/gtk/extension_install_prompt_gtk.cc

 // Copyright (c) 2009 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 <gtk/gtk.h>
 
 #include "app/gfx/gtk_util.h"
 #include "app/l10n_util.h"
 #include "base/rand_util.h"
 #include "base/string_util.h"
@@ skipping 104 matching lines @@
       browser->window());
   if (!browser_window) {
     delegate->AbortInstall();
     return;
   }
 
   std::string warning_ascii = WideToASCII(warning_text);
   ShowInstallPromptDialog(browser_window->window(), icon, extension, delegate,
       warning_ascii);
 }
+
+void ExtensionInstallUI::ShowExtensionInstallError(const std::string& error) {
+  GtkWidget* dialog = gtk_message_dialog_new(NULL, GTK_DIALOG_MODAL,
+      GTK_MESSAGE_ERROR, GTK_BUTTONS_OK, "%s", error.c_str());
+  gtk_window_set_title(GTK_WINDOW(dialog),
+      l10n_util::GetStringUTF8(IDS_EXTENSION_INSTALL_FAILURE_TITLE).c_str());
+  g_signal_connect(dialog, "response", G_CALLBACK(gtk_widget_destroy), NULL);
+  gtk_widget_show_all(dialog);
+}