Content shell/GTK: Add JavaScript dialog support.

content/shell/shell_javascript_dialog.h

Index: content/shell/shell_javascript_dialog.h
diff --git a/content/shell/shell_javascript_dialog.h b/content/shell/shell_javascript_dialog.h
index 12dd8823d65c349a7677bd550e8c0507fd529d22..68fe2ea73ac4ab348676b3043a7ccb7cf2d3129a 100644
--- a/content/shell/shell_javascript_dialog.h
+++ b/content/shell/shell_javascript_dialog.h
@@ -7,6 +7,10 @@
 
 #include "content/public/browser/javascript_dialogs.h"
 
+#if defined(TOOLKIT_GTK)
+#include "ui/base/gtk/gtk_signal.h"
+#endif
+
 #if defined(OS_MACOSX)
 #if __OBJC__
 @class ShellJavaScriptDialogHelper;
@@ -23,6 +27,7 @@ class ShellJavaScriptDialog {
  public:
   ShellJavaScriptDialog(
       ShellJavaScriptDialogCreator* creator,
+      gfx::NativeWindow parent_window,
       JavaScriptMessageType message_type,
       const string16& message_text,
       const string16& default_prompt_text,
@@ -45,6 +50,10 @@ class ShellJavaScriptDialog {
   string16 default_prompt_text_;
   static INT_PTR CALLBACK DialogProc(HWND dialog, UINT message, WPARAM wparam,
                                      LPARAM lparam);
+#elif defined(TOOLKIT_GTK)
+  GtkWidget* gtk_dialog_;
+  gfx::NativeWindow parent_window_;
+  CHROMEGTK_CALLBACK_1(ShellJavaScriptDialog, void, OnResponse, int);
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(ShellJavaScriptDialog);