Add helpers for CGL types.

ui/gl/cgl_util.cc

+// Copyright 2014 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/logging.h"
+#include "ui/gl/cgl_util.h"
+
+namespace gfx {
+
+ScopedCGLSetCurrentContext::ScopedCGLSetCurrentContext(CGLContextObj context)
+  : previous_context_(CGLGetCurrentContext(), base::scoped_policy::RETAIN) {

[Mark Mentovai, 2014/02/07 19:53:41]

4-space indent.

[ccameron, 2014/02/07 20:58:04]

Done.

+  CGLError error = CGLSetCurrentContext(context);
+  DCHECK_EQ(error, kCGLNoError) << "CGLSetCurrentContext should never fail";

[Mark Mentovai, 2014/02/07 19:53:41]

Do you deal with CGLError often? Do you CHECK on them often? If so, it may make
sense to have a whole CGLERROR_LOG family (with CGLERROR_DCHECK) along the lines
of base/mac/mac_logging.h.

This doesn’t need to be a part of this change, and it doesn’t even need to be
done at all, it’s just a suggestion based on past experience.

[ccameron, 2014/02/07 20:58:04]

They're used pretty often, but not CHECKed too often (though perhaps they should
be). I'll keep that in mind.

+}
+
+ScopedCGLSetCurrentContext::~ScopedCGLSetCurrentContext() {
+  CGLError error = CGLSetCurrentContext(previous_context_);
+  DCHECK_EQ(error, kCGLNoError) << "CGLSetCurrentContext should never fail";
+}
+
+}  // namespace gfx