Add method for suppressing MemoryPressureListener notifications

base/memory/memory_pressure_listener.h

 // Copyright 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.
 
 // MemoryPressure provides static APIs for handling memory pressure on
 // platforms that have such signals, such as Android and ChromeOS.
 // The app will try to discard buffers that aren't deemed essential (individual
 // modules will implement their own policy).
 
 #ifndef BASE_MEMORY_MEMORY_PRESSURE_LISTENER_H_
@@ skipping 54 matching lines @@
 
   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);
 
+  // These methods should not be used anywhere else but in memory measurement
+  // code, where they are intended to maintain stable conditions across
+  // measurements.
+  static bool AreNotificationsSuppressed();
+  static void SetNotificationsSuppressed(bool suppressed);
+
  private:
   void Notify(MemoryPressureLevel memory_pressure_level);
 
   MemoryPressureCallback callback_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryPressureListener);
 };
 
 }  // namespace base
 
 #endif  // BASE_MEMORY_MEMORY_PRESSURE_LISTENER_H_