Revert of Port Chromium OS touch noise filtering to Chromium

ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.cc

Index: ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.cc
diff --git a/ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.cc b/ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.cc
deleted file mode 100644
index a1f997f57caa48aad79fe6eb1d88fd985c940356..0000000000000000000000000000000000000000
--- a/ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.cc
+++ /dev/null
@@ -1,91 +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.
-
-#include "ui/events/ozone/evdev/touch_noise/far_apart_taps_touch_noise_filter.h"
-
-#include <cmath>
-
-#include "base/logging.h"
-#include "base/strings/stringprintf.h"
-
-namespace ui {
-
-namespace {
-
-// Minimum squared distance between taps to be considered far apart.
-const int kMinDistance2 = 1500 * 1500;
-
-// Max time between taps considered.
-const int kMaxTapDeltaMs = 30;
-
-// Maximum squared movement of a touch to still be considered a tap.
-const int kMaxTapMovement2 = 20 * 20;
-
-// Returns the squared distance between (|x1|, |y1|) and (|x2|, |y2|).
-int Distance2(int x1, int y1, int x2, int y2) {
-  int offset_x = x2 - x1;
-  int offset_y = y2 - y1;
-  return offset_x * offset_x + offset_y * offset_y;
-}
-
-}  // namespace
-
-void FarApartTapsTouchNoiseFilter::Filter(
-    const std::vector<InProgressTouchEvdev>& touches,
-    base::TimeDelta time,
-    std::bitset<kNumTouchEvdevSlots>* slots_with_noise) {
-  // Remove old taps.
-  base::TimeDelta tap_cutoff =
-      time - base::TimeDelta::FromMilliseconds(kMaxTapDeltaMs);
-  for (size_t i = 0; i < arraysize(tracked_taps_); ++i) {
-    if (tracked_taps_[i].start < tap_cutoff)
-      tracked_taps_[i].Invalidate();
-  }
-
-  for (const InProgressTouchEvdev& touch : touches) {
-    // Only look at slots with active touches.
-    if (!touch.touching && !touch.was_touching)
-      continue;
-
-    size_t slot = touch.slot;
-    if (!touch.was_touching) {
-      // Track new finger info.
-      tracked_taps_[slot] = Tap(time, touch.x, touch.y);
-    } else if (tracked_taps_[slot].is_valid()) {
-      // Check if this finger has moved too far to be considered a tap.
-      if (kMaxTapMovement2 < Distance2(touch.x, touch.y, tracked_taps_[slot].x,
-                                       tracked_taps_[slot].y)) {
-        tracked_taps_[slot].Invalidate();
-      }
-    }
-
-    if (tracked_taps_[slot].is_valid()) {
-      // Check distance from other tracked taps.
-      int min_distance2 = -1;
-      for (size_t i = 0; i < arraysize(tracked_taps_); ++i) {
-        if (i == slot || !tracked_taps_[i].is_valid())
-          continue;
-
-        int dist2 =
-            Distance2(tracked_taps_[i].x, tracked_taps_[i].y, touch.x, touch.y);
-        if (min_distance2 < 0 || dist2 < min_distance2)
-          min_distance2 = dist2;
-      }
-
-      if (min_distance2 > kMinDistance2) {
-        // The other finger should see this one on its next frame and also
-        // get canceled.
-        VLOG(2) << base::StringPrintf(
-            "Cancel tracking id %d %.0fpx from other current taps.",
-            touch.tracking_id, sqrt(min_distance2));
-        slots_with_noise->set(slot);
-      }
-    }
-
-    if (!touch.touching)
-      tracked_taps_[slot].Invalidate();
-  }
-}
-
-}  // namespace ui