Ensure GL initialization only happens once, and provide common init path

ui/aura/demo/demo_main.cc

 // Copyright (c) 2012 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 "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/i18n/icu_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/aura/client/default_capture_client.h"
 #include "ui/aura/client/window_tree_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/test/test_focus_client.h"
 #include "ui/aura/test/test_screen.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/base/hit_test.h"
 #include "ui/compositor/test/context_factories_for_test.h"
 #include "ui/events/event.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/rect.h"
+#include "ui/gl/gl_surface.h"
 
 #if defined(USE_X11)
 #include "base/message_loop/message_pump_x11.h"
 #endif
 
 namespace {
 
 // Trivial WindowDelegate implementation that draws a colored background.
 class DemoWindowDelegate : public aura::WindowDelegate {
  public:
@@ skipping 67 matching lines @@
 
   scoped_ptr<aura::client::DefaultCaptureClient> capture_client_;
 
   DISALLOW_COPY_AND_ASSIGN(DemoWindowTreeClient);
 };
 
 int DemoMain() {
   // Create the message-loop here before creating the root window.
   base::MessageLoopForUI message_loop;
 
+  gfx::GLSurface::InitializeOneOff();
+
   // The ContextFactory must exist before any Compositors are created.
   bool allow_test_contexts = false;
   ui::InitializeContextFactoryForTests(allow_test_contexts);
 
   aura::Env::CreateInstance();
   scoped_ptr<aura::TestScreen> test_screen(aura::TestScreen::Create());
   gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, test_screen.get());
   scoped_ptr<aura::RootWindow> root_window(
       test_screen->CreateRootWindowForPrimaryDisplay());
   scoped_ptr<DemoWindowTreeClient> window_tree_client(new DemoWindowTreeClient(
@@ skipping 39 matching lines @@
 int main(int argc, char** argv) {
   CommandLine::Init(argc, argv);
 
   // The exit manager is in charge of calling the dtors of singleton objects.
   base::AtExitManager exit_manager;
 
   base::i18n::InitializeICU();
 
   return DemoMain();
 }