Make memory pressure notifier configurable

base/memory/memory_pressure_monitor_win.cc

 // 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.
 
 #include "base/memory/memory_pressure_monitor_win.h"
 
 #include <windows.h>
 
 #include "base/metrics/histogram_macros.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 76 matching lines @@
   StartObserving();
 }
 
 MemoryPressureMonitor::MemoryPressureMonitor(int moderate_threshold_mb,
                                              int critical_threshold_mb)
     : moderate_threshold_mb_(moderate_threshold_mb),
       critical_threshold_mb_(critical_threshold_mb),
       current_memory_pressure_level_(
           MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE),
       moderate_pressure_repeat_count_(0),
+      dispatch_callback_(
+          base::Bind(&MemoryPressureListener::NotifyMemoryPressure)),
       weak_ptr_factory_(this) {
   DCHECK_GE(moderate_threshold_mb_, critical_threshold_mb_);
   DCHECK_LE(0, critical_threshold_mb_);
   StartObserving();
 }
 
 MemoryPressureMonitor::~MemoryPressureMonitor() {
   StopObserving();
 }
 
@@ skipping 84 matching lines @@
       break;
   }
 
   if (!notify)
     return;
 
   // Emit a notification of the current memory pressure level. This can only
   // happen for moderate and critical pressure levels.
   DCHECK_NE(MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE,
             current_memory_pressure_level_);
-  MemoryPressureListener::NotifyMemoryPressure(current_memory_pressure_level_);
+  dispatch_callback_.Run(current_memory_pressure_level_);
 }
 
 void MemoryPressureMonitor::CheckMemoryPressureAndRecordStatistics() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   CheckMemoryPressure();
 
   UMA_HISTOGRAM_ENUMERATION(
       "Memory.PressureLevel",
       MemoryPressureLevelToUmaEnumValue(current_memory_pressure_level_),
@@ skipping 31 matching lines @@
 
 bool MemoryPressureMonitor::GetSystemMemoryStatus(
     MEMORYSTATUSEX* mem_status) {
   DCHECK(mem_status != nullptr);
   mem_status->dwLength = sizeof(*mem_status);
   if (!::GlobalMemoryStatusEx(mem_status))
     return false;
   return true;
 }
 
+void MemoryPressureMonitor::SetDispatchCallback(
+    const DispatchCallback& callback) {
+  dispatch_callback_ = callback;
+}
+
 }  // namespace win
 }  // namespace base