arc: Reduce logspam when ARC is not enabled/available

chrome/browser/chromeos/arc/process/arc_process_service.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 CHROME_BROWSER_CHROMEOS_ARC_PROCESS_ARC_PROCESS_SERVICE_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_PROCESS_ARC_PROCESS_SERVICE_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 41 matching lines @@
  public:
   using RequestProcessListCallback =
       base::Callback<void(const std::vector<ArcProcess>&)>;
 
   explicit ArcProcessService(ArcBridgeService* bridge_service);
   ~ArcProcessService() override;
 
   // Returns nullptr before the global instance is ready.
   static ArcProcessService* Get();
 
-  // InstanceHolder<mojom::ProcessInstance>::Observer overrides.
-  void OnInstanceReady() override;
-
   // Returns true if ARC IPC is ready for process list request,
   // otherwise false.
   bool RequestAppProcessList(RequestProcessListCallback callback);
   void RequestSystemProcessList(RequestProcessListCallback callback);
 
   using PidMap = std::map<base::ProcessId, base::ProcessId>;
 
   class NSPidToPidMap : public base::RefCountedThreadSafe<NSPidToPidMap> {
    public:
     NSPidToPidMap();
@@ skipping 21 matching lines @@
     DISALLOW_COPY_AND_ASSIGN(NSPidToPidMap);
   };
 
  private:
   void OnReceiveProcessList(
       const RequestProcessListCallback& callback,
       std::vector<mojom::RunningAppProcessInfoPtr> instance_processes);
 
   scoped_refptr<base::SingleThreadTaskRunner> GetTaskRunner();
 
+  // InstanceHolder<mojom::ProcessInstance>::Observer overrides.
+  void OnInstanceReady() override;
+  void OnInstanceClosed() override;
+
+  // Whether ARC is ready to request its process list.
+  bool instance_ready_ = false;
+
   // There are some expensive tasks such as traverse whole process tree that
   // we can't do it on the UI thread. Thus we need an additional thread to
   // handle
   // such tasks.
   base::Thread heavy_task_thread_;
 
   // Keep a cache pid mapping of all arc processes so to minimize the number of
   // nspid lookup from /proc/<PID>/status.
   // To play safe, always modify |nspid_to_pid_| on the |heavy_task_thread_|.
   scoped_refptr<NSPidToPidMap> nspid_to_pid_;
 
   // Always keep this the last member of this class to make sure it's the
   // first thing to be destructed.
   base::WeakPtrFactory<ArcProcessService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcProcessService);
 };
 
 }  // namespace arc
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_PROCESS_ARC_PROCESS_SERVICE_H_