Refactor direct_memory_pressure_calculator.h per platform.

components/memory_pressure/direct_memory_pressure_calculator.h

Index: components/memory_pressure/direct_memory_pressure_calculator.h
diff --git a/components/memory_pressure/direct_memory_pressure_calculator.h b/components/memory_pressure/direct_memory_pressure_calculator.h
index a2bb60e46a98b470e9a5ecbbd0effebbf9a4cd2e..44258a84dfc02e8d1f2e348021c81bf079383eed 100644
--- a/components/memory_pressure/direct_memory_pressure_calculator.h
+++ b/components/memory_pressure/direct_memory_pressure_calculator.h
@@ -5,75 +5,8 @@
 #ifndef COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_
 #define COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_
 
-#include "components/memory_pressure/memory_pressure_calculator.h"
-
-#include "base/macros.h"
-#include "base/process/process_metrics.h"
-#include "build/build_config.h"
-
-namespace memory_pressure {
-
-#if defined(MEMORY_PRESSURE_IS_POLLING)
-
-// OS-specific implementation of MemoryPressureCalculator. This is only defined
-// and used on platforms that do not have native memory pressure signals
-// (ChromeOS, Linux, Windows). OSes that do have native signals simply hook into
-// the appropriate subsystem (Android, Mac OS X).
-class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
- public:
-#if defined(OS_WIN)
-  // Exposed for unittesting. See .cc file for detailed discussion of these
-  // constants.
-  static const int kLargeMemoryThresholdMb;
-  static const int kSmallMemoryDefaultModerateThresholdMb;
-  static const int kSmallMemoryDefaultCriticalThresholdMb;
-  static const int kLargeMemoryDefaultModerateThresholdMb;
-  static const int kLargeMemoryDefaultCriticalThresholdMb;
-#endif
-
-  // Default constructor. Will choose thresholds automatically based on the
-  // actual amount of system memory installed.
-  DirectMemoryPressureCalculator();
-
-  // Constructor with explicit memory thresholds. These represent the amount of
-  // free memory below which the applicable memory pressure state applies.
-  DirectMemoryPressureCalculator(int moderate_threshold_mb,
-                                 int critical_threshold_mb);
-
-  ~DirectMemoryPressureCalculator() override {}
-
-  // Calculates the current pressure level.
-  MemoryPressureLevel CalculateCurrentPressureLevel() override;
-
-#if defined(OS_WIN)
-  int moderate_threshold_mb() const { return moderate_threshold_mb_; }
-  int critical_threshold_mb() const { return critical_threshold_mb_; }
-#endif
-
- private:
-  friend class TestDirectMemoryPressureCalculator;
-
-  // Gets system memory status. This is virtual as a unittesting hook and by
-  // default this invokes base::GetSystemMemoryInfo.
-  virtual bool GetSystemMemoryInfo(base::SystemMemoryInfoKB* mem_info) const;
-
-#if defined(OS_WIN)
-  // Uses GetSystemMemoryInfo to automatically infer appropriate values for
-  // moderate_threshold_mb_ and critical_threshold_mb_.
-  void InferThresholds();
-
-  // Threshold amounts of available memory that trigger pressure levels. See
-  // memory_pressure_monitor_win.cc for a discussion of reasonable values for
-  // these.
-  int moderate_threshold_mb_;
-  int critical_threshold_mb_;
-#endif
-
-  DISALLOW_COPY_AND_ASSIGN(DirectMemoryPressureCalculator);
-};
-
-#endif  // defined(MEMORY_PRESSURE_IS_POLLING)
-
-}  // namespace memory_pressure
+#ifdef OS_WIN
+#include "components/memory_pressure/direct_memory_pressure_calculator_win.h"
+#endif  // OS_WIN
 
 #endif  // COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_