Moves LowMemoryObserver into chromeos and renames

chromeos/memory/low_memory_listener.h

Index: chromeos/memory/low_memory_listener.h
diff --git a/chromeos/memory/low_memory_listener.h b/chromeos/memory/low_memory_listener.h
new file mode 100644
index 0000000000000000000000000000000000000000..2ecdcd819d1f4f7a0207bf7098e08a4896fc3b94
--- /dev/null
+++ b/chromeos/memory/low_memory_listener.h
@@ -0,0 +1,48 @@
+// Copyright (c) 2013 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 CHROMEOS_MEMORY_LOW_MEMORY_LISTENER_H_
+#define CHROMEOS_MEMORY_LOW_MEMORY_LISTENER_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "chromeos/memory/chromeos_memory_export.h"
+
+namespace chromeos {
+
+class LowMemoryListenerDelegate;
+class LowMemoryListenerImpl;
+
+////////////////////////////////////////////////////////////////////////////////
+// LowMemoryListener
+//
+// Class to handle observation of low memory device for changes so that we
+// can get a signal from the kernel about low memory conditions and notify
+// our delegate, who can take actions such as discarding tabs.
+//
+// This object is intended to be created and used on the UI thread. All
+// notifications are dispatched on the UI thread.
+class CHROMEOS_MEMORY_EXPORT LowMemoryListener {
+ public:
+  explicit LowMemoryListener(LowMemoryListenerDelegate* delegate);
+  ~LowMemoryListener();
+
+  void Start();
+  void Stop();
+
+ private:
+  // Callback from LowMemoryListenerImpl when memory is low. Called on the UI
+  // thread.
+  void OnMemoryLow();
+
+  scoped_refptr<LowMemoryListenerImpl> observer_;
+  LowMemoryListenerDelegate* delegate_;
+  base::WeakPtrFactory<LowMemoryListener> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(LowMemoryListener);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_MEMORY_LOW_MEMORY_LISTENER_H_