Adds a common way to initialize logging

mojo/logging/init_logging.h

+// 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.
+
+#ifndef MOJO_LOGGING_INIT_LOGGING_H_
+#define MOJO_LOGGING_INIT_LOGGING_H_
+
+namespace mojo {
+namespace logging {
+
+// Initializes logging from base::CommandLine.
+void InitLogging();
+
+}  // namespace logging
+}  // namespace mojo
+
+#endif  // MOJO_LOGGING_INIT_LOGGING_H_