Refactor direct_memory_pressure_calculator.h per platform.

components/memory_pressure/direct_memory_pressure_calculator_win.h

Index: components/memory_pressure/direct_memory_pressure_calculator_win.h
diff --git a/components/memory_pressure/direct_memory_pressure_calculator.h b/components/memory_pressure/direct_memory_pressure_calculator_win.h
similarity index 96%
copy from components/memory_pressure/direct_memory_pressure_calculator.h
copy to components/memory_pressure/direct_memory_pressure_calculator_win.h
index a2bb60e46a98b470e9a5ecbbd0effebbf9a4cd2e..10e2d24e285758a1fc1343b596b8a3f122849ed8 100644
--- a/components/memory_pressure/direct_memory_pressure_calculator.h
+++ b/components/memory_pressure/direct_memory_pressure_calculator_win.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_
-#define COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_
+#ifndef COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_WIN_H_
+#define COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_WIN_H_
 
 #include "components/memory_pressure/memory_pressure_calculator.h"
 
@@ -21,7 +21,6 @@ namespace memory_pressure {
 // 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;
@@ -29,7 +28,6 @@ class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
   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.
@@ -45,10 +43,8 @@ class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
   // 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;
@@ -57,7 +53,6 @@ class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
   // 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();
@@ -67,7 +62,6 @@ class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
   // these.
   int moderate_threshold_mb_;
   int critical_threshold_mb_;
-#endif
 
   DISALLOW_COPY_AND_ASSIGN(DirectMemoryPressureCalculator);
 };
@@ -76,4 +70,4 @@ class DirectMemoryPressureCalculator : public MemoryPressureCalculator {
 
 }  // namespace memory_pressure
 
-#endif  // COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_H_
+#endif  // COMPONENTS_MEMORY_PRESSURE_DIRECT_MEMORY_PRESSURE_CALCULATOR_WIN_H_