Merge MemoryCoordinator and MemoryCoordinatorImpl into one class

content/browser/memory/memory_coordinator.h

-// Copyright 2016 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_H_
-#define CONTENT_BROWSER_MEMORY_MEMORY_COORDINATOR_H_
-
-#include "base/memory/memory_coordinator_client_registry.h"
-#include "base/memory/memory_pressure_monitor.h"
-#include "base/process/process_handle.h"
-#include "content/common/content_export.h"
-#include "content/common/memory_coordinator.mojom.h"
-#include "content/public/browser/memory_coordinator_delegate.h"
-#include "mojo/public/cpp/bindings/binding.h"
-
-namespace content {
-
-// NOTE: Memory coordinator is under development and not fully working.
-// TODO(bashi): Add more explanations when we implement memory coordinator V0.
-
-class MemoryCoordinatorHandleImpl;
-
-// MemoryCoordinator is responsible for the whole memory management accross the
-// browser and child proceeses. It dispatches memory events to its clients and
-// child processes based on its best knowledge of the memory usage.
-class CONTENT_EXPORT MemoryCoordinator {
- public:
-  virtual ~MemoryCoordinator();
-
-  // Singleton factory/accessor.
-  static MemoryCoordinator* GetInstance();
-
-  // Starts monitoring memory usage. After calling this method, memory
-  // coordinator will start dispatching state changes.
-  virtual void Start() {}
-
-  // Creates a handle to the provided child process.
-  void CreateHandle(int render_process_id,
-                    mojom::MemoryCoordinatorHandleRequest request);
-
-  // Dispatches a memory state change to the provided process. Returns true if
-  // the process is tracked by this coordinator and successfully dispatches,
-  // returns false otherwise.
-  bool SetChildMemoryState(
-      int render_process_id, mojom::MemoryState memory_state);
-
-  // Returns the memory state of the specified render process. Returns UNKNOWN
-  // if the process is not tracked by this coordinator.
-  mojom::MemoryState GetChildMemoryState(int render_process_id) const;
-
-  // Records memory pressure notifications. Called by MemoryPressureMonitor.
-  // TODO(bashi): Remove this when MemoryPressureMonitor is retired.
-  void RecordMemoryPressure(
-      base::MemoryPressureMonitor::MemoryPressureLevel level);
-
-  // Called when ChildMemoryCoordinator calls AddChild().
-  virtual void OnChildAdded(int render_process_id) {}
-
-  // Returns the global memory state.
-  virtual base::MemoryState GetGlobalMemoryState() const;
-
-  // Returns the browser's current memory state. Note that the current state
-  // could be different from the global memory state as the browser won't be
-  // suspended.
-  virtual base::MemoryState GetCurrentMemoryState() const;
-
-  // Sets the global memory state for testing.
-  virtual void SetCurrentMemoryStateForTesting(base::MemoryState memory_state);
-
- protected:
-  // Constructor. Protected as this is a singleton, but accessible for
-  // unittests.
-  MemoryCoordinator();
-
-  // Adds the given ChildMemoryCoordinator as a child of this coordinator.
-  void AddChildForTesting(int dummy_render_process_id,
-                          mojom::ChildMemoryCoordinatorPtr child);
-
-  // Callback invoked by mojo when the child connection goes down. Exposed
-  // for testing.
-  void OnConnectionError(int render_process_id);
-
-  // Returns true when a given renderer can be suspended.
-  bool CanSuspendRenderer(int render_process_id);
-
-  // Stores information about any known child processes.
-  struct ChildInfo {
-    // This object must be compatible with STL containers.
-    ChildInfo();
-    ChildInfo(const ChildInfo& rhs);
-    ~ChildInfo();
-
-    mojom::MemoryState memory_state;
-    bool is_visible = false;
-    std::unique_ptr<MemoryCoordinatorHandleImpl> handle;
-  };
-
-  // A map from process ID (RenderProcessHost::GetID()) to child process info.
-  using ChildInfoMap = std::map<int, ChildInfo>;
-
-  ChildInfoMap& children() { return children_; }
-
- private:
-#if !defined(OS_MACOSX)
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorTest, HandleAdded);
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorTest, CanSuspendRenderer);
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorTest, CanThrottleRenderer);
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorWithServiceWorkerTest,
-                           CannotSuspendRendererWithServiceWorker);
-#endif
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorTest,
-                           ChildRemovedOnConnectionError);
-  FRIEND_TEST_ALL_PREFIXES(MemoryCoordinatorTest, SetChildMemoryState);
-
-  // Called by SetChildMemoryState() to determine a child memory state based on
-  // the current status of the child process.
-  mojom::MemoryState OverrideGlobalState(mojom::MemoryState memroy_state,
-                                         const ChildInfo& child);
-
-  void SetDelegateForTesting(
-      std::unique_ptr<MemoryCoordinatorDelegate> delegate);
-
-  // Helper function of CreateHandle and AddChildForTesting.
-  void CreateChildInfoMapEntry(
-      int render_process_id,
-      std::unique_ptr<MemoryCoordinatorHandleImpl> handle);
-
-  // Tracks child processes. An entry is added when a renderer connects to
-  // MemoryCoordinator and removed automatically when an underlying binding is
-  // disconnected.
-  ChildInfoMap children_;
-
-  std::unique_ptr<MemoryCoordinatorDelegate> delegate_;
-
-  DISALLOW_COPY_AND_ASSIGN(MemoryCoordinator);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_MEMORY_MEMORY_COORDINATOR_H_