Create base::win::MemoryPressureMonitor class.

base/memory/memory_pressure_monitor.h

Index: base/memory/memory_pressure_monitor.h
diff --git a/base/memory/memory_pressure_monitor.h b/base/memory/memory_pressure_monitor.h
index 9aeeaca3cdca26f0f1376af981000cfeced6aa5b..f115df561b8799564fb78d0a5c49b3f7ef6ed509 100644
--- a/base/memory/memory_pressure_monitor.h
+++ b/base/memory/memory_pressure_monitor.h
@@ -20,6 +20,9 @@ class BASE_EXPORT MemoryPressureMonitor {
  public:
   using MemoryPressureLevel = base::MemoryPressureListener::MemoryPressureLevel;
 
+  // Exposed for use with scoped_ptr.

[grt (UTC plus 2), 2015/05/06 13:26:36]

the fact that you need this for scoped_ptr at the moment is an implementation
detail and is subject to change, so i wouldn't mention it here in a comment. at
a higher level, the dtor must be virtual and public for the sake of polymorphism
so that derived types can have an "is a" relationship with the base class and be
passed around as such. i don't think this needs to be mentioned in a comment,
though, so just remove the comment here.

[chrisha, 2015/05/06 15:09:57]

Done.

+  virtual ~MemoryPressureMonitor();
+
   // Return the singleton MemoryPressureMonitor.
   static MemoryPressureMonitor* Get();
 
@@ -28,7 +31,6 @@ class BASE_EXPORT MemoryPressureMonitor {
 
  protected:
   MemoryPressureMonitor();
-  virtual ~MemoryPressureMonitor();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MemoryPressureMonitor);