Update default policy for memory coordinator

content/browser/memory/memory_coordinator_default_policy.h

 // Copyright 2017 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 CONTENT_BROWSER_MEMORY_MEMORY_COORDINATOR_DEFAULT_POLICY_H_
 #define CONTENT_BROWSER_MEMORY_MEMORY_COORDINATOR_DEFAULT_POLICY_H_
 
 #include "content/browser/memory/memory_coordinator_impl.h"
 
 namespace content {
 
 // The default policy of MemoryCoordinator.
 class MemoryCoordinatorDefaultPolicy : public MemoryCoordinatorImpl::Policy {
  public:
   explicit MemoryCoordinatorDefaultPolicy(MemoryCoordinatorImpl* coordinator);
   ~MemoryCoordinatorDefaultPolicy() override;
 
   void OnCriticalCondition() override;
   void OnConditionChanged(MemoryCondition prev, MemoryCondition next) override;
   void OnChildVisibilityChanged(int render_process_id,
                                 bool is_visible) override;
 
  private:
-  // Set the provided memory_state to all child processes.
-  void SetMemoryStateToAllChildren(MemoryState memory_state);
-
-  enum class PurgeTarget {
-    BACKGROUNDED,
-    ALL,
-  };
-
-  // Tries to find a candidate child process for purging memory and asks the
-  // child to purge memory.
-  bool TryToPurgeMemoryFromChildren(PurgeTarget target);
-
   // Not owned.
   MemoryCoordinatorImpl* coordinator_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MEMORY_MEMORY_COORDINATOR_DEFAULT_POLICY_H_