Adds MemoryPressureListener.

base/android/memory_pressure_android.h

Index: base/android/memory_pressure_android.h
diff --git a/base/android/memory_pressure_android.h b/base/android/memory_pressure_android.h
new file mode 100644
index 0000000000000000000000000000000000000000..d84d191fa22e20c6fa4747f8c11f8c3d1eb8cad3
--- /dev/null
+++ b/base/android/memory_pressure_android.h
@@ -0,0 +1,30 @@
+// 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 BASE_ANDROID_MEMORY_PRESSURE_ANDROID_H_
+#define BASE_ANDROID_MEMORY_PRESSURE_ANDROID_H_
+
+#include "base/android/jni_android.h"
+
+namespace base {
+namespace android {
+
+// Implements the C++ counter part of MemoryPressure.java
+class MemoryPressureAndroid {
+ public:
+  static bool Register(JNIEnv* env);
+
+  static void RegisterSystemCallback(JNIEnv* env);
+
+  // Called by JNI.
+  static void OnMemoryPressure(int memory_pressure_type);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MemoryPressureAndroid);
+};
+
+}  // namespace android
+}  // namespace base
+
+#endif  // BASE_ANDROID_MEMORY_PRESSURE_ANDROID_H_