[memory-infra] Move periodic timer to dump thread

base/trace_event/memory_dump_scheduler.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 BASE_TRACE_EVENT_MEMORY_DUMP_SCHEDULER_H
 #define BASE_TRACE_EVENT_MEMORY_DUMP_SCHEDULER_H
 
 #include <memory>
 
 #include "base/base_export.h"
@@ skipping 60 matching lines @@
 
     RepeatingTimer timer;
     uint32_t dump_count;
     uint32_t min_timer_period_ms;
     uint32_t light_dumps_rate;
     uint32_t heavy_dumps_rate;
 
     uint32_t light_dump_period_ms;
     uint32_t heavy_dump_period_ms;
 
+    bool is_enabled_for_testing;
+
     DISALLOW_COPY_AND_ASSIGN(PeriodicTriggerState);
   };
 
   struct BASE_EXPORT PollingTriggerState {
     enum State {
       CONFIGURED,  // Polling trigger was added.
       ENABLED,     // Polling is running.
       DISABLED     // Polling is disabled.
     };
 
@@ skipping 19 matching lines @@
     int64_t memory_increase_threshold;
     uint64_t last_memory_totals_kb[kMaxNumMemorySamples];
     uint32_t last_memory_totals_kb_index;
 
     DISALLOW_COPY_AND_ASSIGN(PollingTriggerState);
   };
 
   MemoryDumpScheduler();
   ~MemoryDumpScheduler();
 
+  // Helper to enable timer on polling thread.
+  void EnablePeriodicTimerOnPollingThread();
+
   // Helper to set polling disabled.
-  void DisablePollingOnPollingThread();
+  void DisableTriggersOnPollingThread();
 
   // Periodically called by the timer.
   void RequestPeriodicGlobalDump();
 
   // Called for polling memory usage and trigger dumps if peak is detected.
   void PollMemoryOnPollingThread();
 
   // Returns true if peak memory value is detected.
   bool ShouldTriggerDump(uint64_t current_memory_total);
 
   // Helper to detect peaks in memory usage.
   bool IsCurrentSamplePeak(uint64_t current_memory_total);
 
   // Must be set before enabling tracing.
   static void SetPollingIntervalForTesting(uint32_t interval);
 
   // True if periodic dumping is enabled.
   bool IsPeriodicTimerRunningForTesting();
 
+  // Timer.Start is not called if disabled, for tests without message loop.
+  void DisablePeriodicTimerForTesting(bool disable);
+
   MemoryDumpManager* mdm_;
 
   // Accessed on the thread of the client before enabling and only accessed on
-  // the thread that called "EnablePeriodicTriggersIfNeeded()" after enabling.
+  // the polling thread after enabling:
   std::unique_ptr<PeriodicTriggerState> periodic_state_;
-
-  // Accessed on the thread of the client before enabling and only accessed on
-  // the polling thread after enabling.
   std::unique_ptr<PollingTriggerState> polling_state_;
 
   // Accessed on the thread of the client only.
   scoped_refptr<SingleThreadTaskRunner> polling_task_runner_;
 
   // True when the scheduler is setup. Accessed on the thread of client only.
   bool is_setup_;
 
+  // Disables the Timer.Start for periodic triggers.
+  static bool periodic_timer_disabled_for_testing_;
+
   DISALLOW_COPY_AND_ASSIGN(MemoryDumpScheduler);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_SCHEDULER_H