LibGL: Add simple implementation of buffer objects

For now, buffers are only implemented on the LibGL side, however in the
future buffer objects should be stored in LibGPU.

Userland/Libraries/LibGL/Buffer/Buffer.cpp

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2022, cflip <cflip@cflip.net>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "Buffer.h"
+
+namespace GL {
+
+ErrorOr<void> Buffer::set_data(void const* data, size_t size)
+{
+    if (!data) {
+        m_data = TRY(ByteBuffer::create_uninitialized(size));
+        return {};
+    }
+    m_data = TRY(ByteBuffer::copy(data, size));
+    return {};
+}
+
+void Buffer::replace_data(void const* data, size_t offset, size_t size)
+{
+    m_data.overwrite(offset, data, size);
+}
+
+size_t Buffer::size()
+{
+    return m_data.size();
+}
+
+void* Buffer::data()
+{
+    return m_data.data();
+}
+
+void* Buffer::offset_data(size_t offset)
+{
+    return m_data.offset_pointer(offset);
+}
+
+}