Mojo: Make GetDefault{AsyncWaiter,Logger} static methods of Environment.

mojo/public/cpp/environment/lib/default_async_waiter.h

Index: mojo/public/cpp/environment/lib/default_async_waiter.h
diff --git a/mojo/public/cpp/environment/lib/default_async_waiter.h b/mojo/public/cpp/environment/lib/default_async_waiter.h
new file mode 100644
index 0000000000000000000000000000000000000000..49ce233490ca12ca676c297ae7b775978acabf32
--- /dev/null
+++ b/mojo/public/cpp/environment/lib/default_async_waiter.h
@@ -0,0 +1,18 @@
+// 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.
+
+#ifndef MOJO_PUBLIC_CPP_ENVIRONMENT_LIB_DEFAULT_ASYNC_WAITER_H_
+#define MOJO_PUBLIC_CPP_ENVIRONMENT_LIB_DEFAULT_ASYNC_WAITER_H_
+
+struct MojoAsyncWaiter;
+
+namespace mojo {
+namespace internal {
+
+extern const MojoAsyncWaiter kDefaultAsyncWaiter;
+
+}  // namespace internal
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_ENVIRONMENT_LIB_DEFAULT_ASYNC_WAITER_H_