Remove memory_pressure component.

components/memory_pressure/filtered_memory_pressure_calculator.h

Index: components/memory_pressure/filtered_memory_pressure_calculator.h
diff --git a/components/memory_pressure/filtered_memory_pressure_calculator.h b/components/memory_pressure/filtered_memory_pressure_calculator.h
deleted file mode 100644
index 722f491cf682a43c0ac2bf2339c1bc92c24bb016..0000000000000000000000000000000000000000
--- a/components/memory_pressure/filtered_memory_pressure_calculator.h
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2015 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 COMPONENTS_MEMORY_PRESSURE_FILTERED_MEMORY_PRESSURE_CALCULATOR_H_
-#define COMPONENTS_MEMORY_PRESSURE_FILTERED_MEMORY_PRESSURE_CALCULATOR_H_
-
-#include "components/memory_pressure/memory_pressure_calculator.h"
-
-#include "base/macros.h"
-#include "base/time/time.h"
-
-namespace base {
-class TickClock;
-}  // namespace base
-
-namespace memory_pressure {
-
-#if defined(MEMORY_PRESSURE_IS_POLLING)
-
-// A utility class that provides rate-limiting and hysteresis on raw memory
-// pressure calculations. This is identical across all platforms, but only used
-// on those that do not have native memory pressure signals.
-class FilteredMemoryPressureCalculator : public MemoryPressureCalculator {
- public:
-  // The cooldown period when transitioning from critical to moderate/no memory
-  // pressure, or from moderate to none.
-  //
-  // These values were experimentally obtained during the initial ChromeOS only
-  // implementation of this feature. By spending a significant cooldown period
-  // at a higher pressure level more time is dedicated to freeing resources and
-  // less churn occurs in the MemoryPressureListener event stream.
-  enum : int { kCriticalPressureCooldownPeriodMs = 5000 };
-  enum : int { kModeratePressureCooldownPeriodMs = 5000 };
-
-  // The provided |pressure_calculator| and |tick_clock| must outlive this
-  // object.
-  FilteredMemoryPressureCalculator(
-      MemoryPressureCalculator* pressure_calculator,
-      base::TickClock* tick_clock);
-  ~FilteredMemoryPressureCalculator() override;
-
-  // Calculates the current pressure level.
-  MemoryPressureLevel CalculateCurrentPressureLevel() override;
-
-  // Accessors for unittesting.
-  bool cooldown_in_progress() const { return cooldown_in_progress_; }
-  base::TimeTicks cooldown_start_time() const { return cooldown_start_time_; }
-  MemoryPressureLevel cooldown_high_tide() const { return cooldown_high_tide_; }
-
- private:
-  friend class TestFilteredMemoryPressureCalculator;
-
-  // The delegate pressure calculator. Provided by the constructor.
-  MemoryPressureCalculator* pressure_calculator_;
-
-  // The delegate tick clock. Provided by the constructor.
-  base::TickClock* tick_clock_;
-
-  // The memory pressure currently being reported.
-  MemoryPressureLevel current_pressure_level_;
-
-  // The last time a sample was taken.
-  bool samples_taken_;
-  base::TimeTicks last_sample_time_;
-
-  // State of an ongoing cooldown period, if any. The high-tide line indicates
-  // the highest memory pressure level (*below* the current one) that was
-  // encountered during the cooldown period. This allows a cooldown to
-  // transition directly from critical to none if *no* moderate pressure signals
-  // were seen during the period, otherwise it forces it to pass through a
-  // moderate cooldown as well.
-  bool cooldown_in_progress_;
-  base::TimeTicks cooldown_start_time_;
-  MemoryPressureLevel cooldown_high_tide_;
-
-  DISALLOW_COPY_AND_ASSIGN(FilteredMemoryPressureCalculator);
-};
-
-#endif  // defined(MEMORY_PRESSURE_IS_POLLING)
-
-}  // namespace memory_pressure
-
-#endif  // COMPONENTS_MEMORY_PRESSURE_FILTERED_MEMORY_PRESSURE_CALCULATOR_H_