Add GetProcAddress to OpenGL control interface

mojo/gles2/mgl_unittest.cc

Index: mojo/gles2/mgl_unittest.cc
diff --git a/mojo/gles2/mgl_unittest.cc b/mojo/gles2/mgl_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..244044e51963d1b9c1f6b0fdfad248fdc2b7119a
--- /dev/null
+++ b/mojo/gles2/mgl_unittest.cc
@@ -0,0 +1,20 @@
+// 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/c/gpu/MGL/mgl.h"
+
+#include <string.h>
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace mojo {
+namespace {
+
+TEST(MGLTest, GetProcAddress) {
+  EXPECT_EQ(nullptr, MGLGetProcAddress(""));
+  EXPECT_NE(nullptr, MGLGetProcAddress("glActiveTexture"));
+}
+
+}  // namespace
+}  // namespace mojo