Use C OpenGL interface in mojo::GLContext

mojo/public/platform/native/gles2_impl_chromium_map_sub_thunks.cc

+// Copyright 2015 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 "mojo/public/platform/native/gles2_impl_chromium_map_sub_thunks.h"
+
+#include <assert.h>
+
+#include "mojo/public/platform/native/thunk_export.h"
+
+extern "C" {
+static MojoGLES2ImplChromiumMapSubThunks g_impl_chromium_map_sub_thunks = {0};
+
+#define VISIT_GL_CALL(Function, ReturnType, PARAMETERS, ARGUMENTS) \
+  ReturnType GL_APIENTRY gl##Function PARAMETERS {                 \
+    assert(g_impl_chromium_map_sub_thunks.Function);               \
+    return g_impl_chromium_map_sub_thunks.Function ARGUMENTS;      \
+  }
+#include "mojo/public/c/gles2/gles2_call_visitor_chromium_map_sub_autogen.h"
+#undef VISIT_GL_CALL
+
+extern "C" THUNK_EXPORT size_t
+MojoSetGLES2ImplChromiumMapSubThunks(const MojoGLES2ImplChromiumMapSubThunks*
+                                         gles2_impl_chromium_map_sub_thunks) {
+  if (gles2_impl_chromium_map_sub_thunks->size >=
+      sizeof(g_impl_chromium_map_sub_thunks))
+    g_impl_chromium_map_sub_thunks = *gles2_impl_chromium_map_sub_thunks;
+  return sizeof(g_impl_chromium_map_sub_thunks);
+}
+
+}  // extern "C"