Don't crash on invalid URL in GTK ContentShell

content/shell/browser/shell_gtk.cc

 // Copyright 2013 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 "content/shell/browser/shell.h"
 
 #include <gdk/gdkkeysyms.h>
 #include <gtk/gtk.h>
 
 #include "base/logging.h"
@@ skipping 263 matching lines @@
 
 void Shell::OnStopButtonClicked(GtkWidget* widget) {
   Stop();
 }
 
 void Shell::OnURLEntryActivate(GtkWidget* entry) {
   const gchar* str = gtk_entry_get_text(GTK_ENTRY(entry));
   GURL url(str);
   if (!url.has_scheme())
     url = GURL(std::string("http://") + std::string(str));
-  LoadURL(GURL(url));
+  if (url.is_valid())
+    LoadURL(url);
 }
 
 // Callback for when the main window is destroyed.
 gboolean Shell::OnWindowDestroyed(GtkWidget* window) {
   delete this;
   return FALSE;  // Don't stop this message.
 }
 
 gboolean Shell::OnCloseWindowKeyPressed(GtkAccelGroup* accel_group,
                                         GObject* acceleratable,
@@ skipping 35 matching lines @@
 
 void Shell::PlatformSetTitle(const string16& title) {
   if (headless_)
     return;
 
   std::string title_utf8 = UTF16ToUTF8(title);
   gtk_window_set_title(GTK_WINDOW(window_), title_utf8.c_str());
 }
 
 }  // namespace content