Linux: fix broken build by forward-declaring GdkPixbuf.

chrome/browser/gtk/create_application_shortcuts_dialog_gtk.h

 // 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.
 
 #ifndef CHROME_BROWSER_GTK_CREATE_APPLICATION_SHORTCUTS_DIALOG_GTK_H_
 #define CHROME_BROWSER_GTK_CREATE_APPLICATION_SHORTCUTS_DIALOG_GTK_H_
 
 #include "app/gtk_signal.h"
 #include "base/basictypes.h"
 #include "base/ref_counted.h"
 #include "base/string16.h"
 #include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/shell_integration.h"
 #include "googleurl/src/gurl.h"
 
+typedef struct _GdkPixbuf GdkPixbuf;
 typedef struct _GtkWidget GtkWidget;
 typedef struct _GtkWindow GtkWindow;
 
 class TabContents;
 
 class CreateApplicationShortcutsDialogGtk
     : public base::RefCountedThreadSafe<CreateApplicationShortcutsDialogGtk,
                                         ChromeThread::DeleteOnUIThread> {
  public:
   // Displays the dialog box to create application shortcuts for |tab_contents|.
@@ skipping 36 matching lines @@
   // Dialog box that allows the user to create an application shortcut.
   GtkWidget* create_dialog_;
 
   // Dialog box that shows the error message.
   GtkWidget* error_dialog_;
 
   DISALLOW_COPY_AND_ASSIGN(CreateApplicationShortcutsDialogGtk);
 };
 
 #endif  // CHROME_BROWSER_GTK_CREATE_APPLICATION_SHORTCUTS_DIALOG_GTK_H_