Remove memory_pressure component.

components/memory_pressure/memory_pressure_listener.h

Index: components/memory_pressure/memory_pressure_listener.h
diff --git a/components/memory_pressure/memory_pressure_listener.h b/components/memory_pressure/memory_pressure_listener.h
deleted file mode 100644
index d0efd3b7b8f98043adeb95cefe29f55cf848b521..0000000000000000000000000000000000000000
--- a/components/memory_pressure/memory_pressure_listener.h
+++ /dev/null
@@ -1,92 +0,0 @@
-// 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.
-
-// MemoryPressureListener provides static APIs for handling memory pressure on
-// platforms that have such signals (Android, ChromeOS, Mac and Windows). When
-// such signals are received the app will try to discard buffers that aren't
-// deemed essential (individual modules will implement their own policy).
-
-#ifndef COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_LISTENER_H_
-#define COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_LISTENER_H_
-
-#include "base/base_export.h"
-#include "base/callback.h"
-#include "base/macros.h"
-#include "build/build_config.h"
-
-// Other operating systems will be added to this as they are implemented.
-#if defined(OS_WIN) || defined(OS_LINUX)
-#define MEMORY_PRESSURE_IS_POLLING
-#endif
-
-namespace memory_pressure {
-
-// To start listening, create a new instance, passing a callback to a
-// function that takes a MemoryPressureLevel parameter. To stop listening,
-// simply delete the listener object. The implementation guarantees
-// that the callback will always be called on the thread that created
-// the listener.
-//
-// Note that even on the same thread, the callback is not guaranteed to be
-// called synchronously within the system memory pressure broadcast.
-// Please see notes in MemoryPressureLevel enum below: some levels are
-// absolutely critical, and if not enough memory is returned to the system,
-// it'll potentially kill the app, and then later the app will have to be
-// cold-started.
-//
-// Example:
-//
-//   void OnMemoryPressure(MemoryPressureLevel memory_pressure_level) {
-//     ...
-//   }
-//
-//   // Start listening.
-//   MemoryPressureListener* my_listener =
-//       new MemoryPressureListener(base::Bind(&OnMemoryPressure));
-//
-//   ...
-//
-//   // Stop listening.
-//   delete my_listener;
-//
-class MemoryPressureListener {
- public:
-  // A Java counterpart will be generated for this enum.
-  // GENERATED_JAVA_ENUM_PACKAGE: org.chromium.base
-  enum MemoryPressureLevel {
-    // No problems, there is enough memory to use. This event is not sent via
-    // callback, but the enum is used in other places to find out the current
-    // state of the system.
-    MEMORY_PRESSURE_LEVEL_NONE = -1,
-
-    // Modules are advised to free buffers that are cheap to re-allocate and not
-    // immediately needed.
-    MEMORY_PRESSURE_LEVEL_MODERATE = 0,
-
-    // At this level, modules are advised to free all possible memory.  The
-    // alternative is to be killed by the system, which means all memory will
-    // have to be re-created, plus the cost of a cold start.
-    MEMORY_PRESSURE_LEVEL_CRITICAL = 2,
-  };
-
-  typedef base::Callback<void(MemoryPressureLevel)> MemoryPressureCallback;
-
-  explicit MemoryPressureListener(
-      const MemoryPressureCallback& memory_pressure_callback);
-  ~MemoryPressureListener();
-
-  // Intended for use by the platform specific implementation.
-  static void NotifyMemoryPressure(MemoryPressureLevel memory_pressure_level);
-
- private:
-  void Notify(MemoryPressureLevel memory_pressure_level);
-
-  MemoryPressureCallback callback_;
-
-  DISALLOW_COPY_AND_ASSIGN(MemoryPressureListener);
-};
-
-}  // namespace memory_pressure
-
-#endif  // COMPONENTS_MEMORY_PRESSURE_MEMORY_PRESSURE_LISTENER_H_