Add IsCurrentlyLowMemory

third_party/WebKit/Source/platform/MemoryCoordinator.h

 // 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.
 
 #ifndef MemoryCoordinator_h
 #define MemoryCoordinator_h
 
 #include "platform/PlatformExport.h"
 #include "platform/heap/Handle.h"
 #include "platform/wtf/Noncopyable.h"
@@ skipping 27 matching lines @@
   // Whether the device Blink runs on is a low-end device.
   // Can be overridden in layout tests via internals.
   static bool IsLowEndDevice();
 
   // Returns the amount of physical memory in megabytes on the device.
   static int64_t GetPhysicalMemoryMB();
 
   // Override the value of the physical memory for testing.
   static void SetPhysicalMemoryMBForTesting(int64_t);
 
+  // Returns true when available memory is low.
+  // This is not cheap and should not be called repeatedly.
+  // TODO(keishi): Remove when MemoryState is ready.
+  static bool IsCurrentlyLowMemory();
+
   // Caches whether this device is a low-end device and the device physical
   // memory in static members. instance() is not used as it's a heap allocated
   // object - meaning it's not thread-safe as well as might break tests counting
   // the heap size.
   static void Initialize();
 
   void RegisterClient(MemoryCoordinatorClient*);
   void UnregisterClient(MemoryCoordinatorClient*);
 
   // TODO(bashi): Deprecating. Remove this when MemoryPressureListener is
@@ skipping 17 matching lines @@
 
   static bool is_low_end_device_;
   static int64_t physical_memory_mb_;
 
   HeapHashSet<WeakMember<MemoryCoordinatorClient>> clients_;
 };
 
 }  // namespace blink
 
 #endif  // MemoryCoordinator_h