Allow overriding of X error functions

app/x11_util_internal.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 APP_X11_UTIL_INTERNAL_H_
 #define APP_X11_UTIL_INTERNAL_H_
 #pragma once
 
 // This file declares utility functions for X11 (Linux only).
 //
 // These functions require the inclusion of the Xlib headers. Since the Xlib
 // headers pollute so much of the namespace, this should only be included
 // when needed.
 
 extern "C" {
 #include <X11/Xatom.h>
 #include <X11/Xlib.h>
 #include <X11/extensions/XShm.h>
 #include <X11/extensions/Xrender.h>
 }
 
 namespace x11_util {
-  // NOTE: these function caches the results and must be called from the UI
+  // --------------------------------------------------------------------------
+  // NOTE: these functions cache the results and must be called from the UI
   // thread.
-
   // Get the XRENDER format id for ARGB32 (Skia's format).
   //
   // NOTE:Currently this don't support multiple screens/displays.
   XRenderPictFormat* GetRenderARGB32Format(Display* dpy);
 
   // Get the XRENDER format id for the default visual on the first screen. This
   // is the format which our GTK window will have.
   XRenderPictFormat* GetRenderVisualFormat(Display* dpy, Visual* visual);
+
+  // --------------------------------------------------------------------------
+  // X11 error handling.
+  // Sets the X Error Handlers. Passing NULL for either will enable the default
+  // error handler, which if called will log the error and abort the process.
+  void SetX11ErrorHandlers(XErrorHandler error_handler,
+                           XIOErrorHandler io_error_handler);
+
+  // Returns a string suitable for logging the error event.
+  std::string GetErrorEventDescription(XErrorEvent* error_event);
 };
 
 #endif  // APP_X11_UTIL_INTERNAL_H_