Do not allow split view to be engaged by a bezel gesture

athena/wm/bezel_controller.cc

Index: athena/wm/bezel_controller.cc
diff --git a/athena/wm/bezel_controller.cc b/athena/wm/bezel_controller.cc
deleted file mode 100644
index 6924aa603957faa6c09563beb0d0ae0c53dde850..0000000000000000000000000000000000000000
--- a/athena/wm/bezel_controller.cc
+++ /dev/null
@@ -1,209 +0,0 @@
-// Copyright 2014 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 "athena/wm/bezel_controller.h"
-
-#include "ui/aura/window.h"
-#include "ui/events/event_handler.h"
-#include "ui/gfx/display.h"
-#include "ui/gfx/geometry/point_conversions.h"
-#include "ui/gfx/screen.h"
-#include "ui/wm/core/coordinate_conversion.h"
-
-namespace athena {
-namespace {
-
-// Using bezel swipes, the first touch that is registered is usually within
-// 5-10 pixels from the edge, but sometimes as far as 29 pixels away.
-// So setting this width fairly high for now.
-const float kBezelWidth = 20.0f;
-
-const float kScrollDeltaNone = 0;
-
-bool ShouldProcessGesture(ui::EventType event_type) {
-  return event_type == ui::ET_GESTURE_SCROLL_UPDATE ||
-         event_type == ui::ET_GESTURE_SCROLL_BEGIN ||
-         event_type == ui::ET_GESTURE_BEGIN ||
-         event_type == ui::ET_GESTURE_END;
-}
-
-gfx::Display GetDisplay(aura::Window* window) {
-  gfx::Screen* screen = gfx::Screen::GetScreenFor(window);
-  return screen->GetDisplayNearestWindow(window);
-}
-
-float GetDistance(const gfx::PointF& location,
-                  aura::Window* window,
-                  BezelController::Bezel bezel) {
-  DCHECK(bezel == BezelController::BEZEL_LEFT ||
-         bezel == BezelController::BEZEL_RIGHT);
-  // Convert location from window coordinates to screen coordinates.
-  gfx::Point point_in_screen(gfx::ToRoundedPoint(location));
-  wm::ConvertPointToScreen(window, &point_in_screen);
-  return bezel == BezelController::BEZEL_LEFT
-             ? point_in_screen.x()
-             : point_in_screen.x() - GetDisplay(window).bounds().width();
-}
-
-// Returns the bezel corresponding to the |location| in |window| or BEZEL_NONE
-// if the location is outside of the bezel area.
-// Only implemented for LEFT and RIGHT bezels.
-BezelController::Bezel GetBezel(const gfx::PointF& location,
-                                aura::Window* window) {
-  int screen_width = GetDisplay(window).bounds().width();
-  gfx::Point point_in_screen(gfx::ToRoundedPoint(location));
-  wm::ConvertPointToScreen(window, &point_in_screen);
-  if (point_in_screen.x() < kBezelWidth)
-    return BezelController::BEZEL_LEFT;
-  if (point_in_screen.x() > screen_width - kBezelWidth)
-    return BezelController::BEZEL_RIGHT;
-  return BezelController::BEZEL_NONE;
-}
-
-}  // namespace
-
-BezelController::BezelController(aura::Window* container)
-    : container_(container),
-      state_(NONE),
-      scroll_bezel_(BEZEL_NONE),
-      scroll_target_(nullptr),
-      left_right_delegate_(nullptr) {
-}
-
-void BezelController::SetState(BezelController::State state) {
-  // Use SetState(State, float) if |state| is one of the BEZEL_SCROLLING states.
-  DCHECK_NE(state, BEZEL_SCROLLING_TWO_FINGERS);
-  DCHECK_NE(state, BEZEL_SCROLLING_ONE_FINGER);
-  SetState(state, kScrollDeltaNone);
-}
-
-void BezelController::SetState(BezelController::State state,
-                               float scroll_delta) {
-  if (!left_right_delegate_ || state == state_)
-    return;
-
-  State old_state = state_;
-  state_ = state;
-
-  if (state == NONE) {
-    scroll_bezel_ = BEZEL_NONE;
-    scroll_target_ = nullptr;
-  }
-
-  if (state == BEZEL_SCROLLING_TWO_FINGERS) {
-    left_right_delegate_->BezelScrollBegin(scroll_bezel_, scroll_delta);
-  } else if (old_state == BEZEL_SCROLLING_TWO_FINGERS) {
-    // If BezelScrollEnd() hides |scroll_target_|, ET_GESTURE_END is dispatched
-    // and we get a reentrant call to SetState().
-    left_right_delegate_->BezelScrollEnd(0.0f);
-  }
-}
-
-void BezelController::OnGestureEvent(ui::GestureEvent* event) {
-  // TODO(mfomitchev): Currently we aren't retargetting or consuming any of the
-  // touch events. This means that content can prevent the generation of gesture
-  // events and two-finger scroll won't work. Possible solution to this problem
-  // is hosting our own gesture recognizer or retargetting touch events at the
-  // bezel.
-
-  if (!left_right_delegate_)
-    return;
-
-  ui::EventType type = event->type();
-  if (!ShouldProcessGesture(type))
-    return;
-
-  const ui::GestureEventDetails& event_details = event->details();
-  int num_touch_points = event_details.touch_points();
-  if (num_touch_points == 1 && type == ui::ET_GESTURE_BEGIN) {
-    // Reset the state when the first finger touches and starts a gesture.
-    // Normally, the state gets reset when the last finger is lifted and we
-    // receive ET_GESTURE_END. However ET_GESTURE_END doesn't always get
-    // dispatched. (E.g. if the gesture target was hidden or deleted).
-    // Since we can't rely on receiving ET_GESTURE_END when the last finger is
-    // lifted, we also reset the state on ET_GESTURE_BEGIN when the first
-    // finger touches the screen.
-    SetState(NONE);
-  }
-
-  if (scroll_target_ && event->target() != scroll_target_)
-    return;
-
-  const gfx::PointF& event_location = event->location_f();
-  float scroll_delta = kScrollDeltaNone;
-  aura::Window* target_window = static_cast<aura::Window*>(event->target());
-  if (scroll_bezel_ != BEZEL_NONE)
-    scroll_delta = GetDistance(event_location, target_window, scroll_bezel_);
-
-  if (type == ui::ET_GESTURE_BEGIN) {
-    if (num_touch_points > 2) {
-      SetState(IGNORE_CURRENT_SCROLL);
-      return;
-    }
-    BezelController::Bezel event_bezel =
-        GetBezel(event->location_f(), target_window);
-    switch (state_) {
-      case NONE:
-        scroll_bezel_ = event_bezel;
-        scroll_target_ = event->target();
-        if (event_bezel != BEZEL_LEFT && event_bezel != BEZEL_RIGHT)
-          SetState(IGNORE_CURRENT_SCROLL);
-        else
-          SetState(BEZEL_GESTURE_STARTED);
-        break;
-      case IGNORE_CURRENT_SCROLL:
-        break;
-      case BEZEL_GESTURE_STARTED:
-      case BEZEL_SCROLLING_ONE_FINGER:
-        DCHECK_EQ(num_touch_points, 2);
-        DCHECK(scroll_target_);
-        DCHECK_NE(scroll_bezel_, BEZEL_NONE);
-
-        if (event_bezel != scroll_bezel_) {
-          SetState(IGNORE_CURRENT_SCROLL);
-          return;
-        }
-        if (state_ == BEZEL_SCROLLING_ONE_FINGER)
-          SetState(BEZEL_SCROLLING_TWO_FINGERS);
-        break;
-      case BEZEL_SCROLLING_TWO_FINGERS:
-        // Should've exited above
-        NOTREACHED();
-        break;
-    }
-  } else if (type == ui::ET_GESTURE_END) {
-    if (state_ == NONE)
-      return;
-
-    CHECK(scroll_target_);
-    if (num_touch_points == 1) {
-      SetState(NONE);
-    } else {
-      SetState(IGNORE_CURRENT_SCROLL);
-    }
-  } else if (type == ui::ET_GESTURE_SCROLL_BEGIN) {
-    DCHECK(state_ == IGNORE_CURRENT_SCROLL || state_ == BEZEL_GESTURE_STARTED);
-    if (state_ != BEZEL_GESTURE_STARTED)
-      return;
-
-    if (num_touch_points == 1) {
-      SetState(BEZEL_SCROLLING_ONE_FINGER, scroll_delta);
-      return;
-    }
-
-    DCHECK_EQ(num_touch_points, 2);
-    SetState(BEZEL_SCROLLING_TWO_FINGERS, scroll_delta);
-    if (left_right_delegate_->BezelCanScroll())
-      event->SetHandled();
-  } else if (type == ui::ET_GESTURE_SCROLL_UPDATE) {
-    if (state_ != BEZEL_SCROLLING_TWO_FINGERS)
-      return;
-
-    left_right_delegate_->BezelScrollUpdate(scroll_delta);
-    if (left_right_delegate_->BezelCanScroll())
-      event->SetHandled();
-  }
-}
-
-}  // namespace athena