Make the workspace cycler animation parameters editable via chrome://gesture

ash/wm/workspace/workspace_cycler.cc

 // Copyright (c) 2012 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 "ash/wm/workspace/workspace_cycler.h"
 
 #include <cmath>
 
 #include "ash/shell.h"
+#include "ash/wm/workspace/workspace_cycler_configuration.h"
 #include "ash/wm/workspace/workspace_manager.h"
 #include "ui/base/events/event.h"
 #include "ui/base/events/event_utils.h"
 
+typedef ash::WorkspaceCyclerConfiguration Config;
+
 namespace ash {
 namespace internal {
 
 namespace {
 
-// The required vertical distance to initiate workspace cycling.
-const float kDistanceToInitiateWorkspaceCycling = 10.0f;
-
 // Returns true if cycling is allowed.
 bool IsCyclingAllowed() {
   // Cycling is disabled if the screen is locked or a modal dialog is open.
   return !Shell::GetInstance()->IsScreenLocked() &&
          !Shell::GetInstance()->IsSystemModalWindowOpen();
 }
 
 }  // namespace
 
 WorkspaceCycler::WorkspaceCycler(WorkspaceManager* workspace_manager)
@@ skipping 94 matching lines @@
 
   if (ui::IsNaturalScrollEnabled()) {
     scroll_x_ += event->x_offset();
     scroll_y_ += event->y_offset();
   } else {
     scroll_x_ -= event->x_offset();
     scroll_y_ -= event->y_offset();
   }
 
   if (state_ == NOT_CYCLING_TRACKING_SCROLL) {
-    if (fabs(scroll_x_) > kDistanceToInitiateWorkspaceCycling) {
+    double distance_to_initiate_cycling = Config::GetDouble(
+        Config::DISTANCE_TO_INITIATE_CYCLING);
+
+    if (fabs(scroll_x_) > distance_to_initiate_cycling) {
       // Only initiate workspace cycling if there recently was a significant
       // amount of vertical movement as opposed to vertical movement
       // accumulated over a long horizontal three finger scroll.
       scroll_x_ = 0.0f;
       scroll_y_ = 0.0f;
     }
 
-    if (fabs(scroll_y_) >= kDistanceToInitiateWorkspaceCycling)
+    if (fabs(scroll_y_) >= distance_to_initiate_cycling)
       SetState(STARTING_CYCLING);
   }
 
   if (state_ == CYCLING && event->y_offset() != 0.0f) {
     DCHECK(animator_.get());
     animator_->AnimateCyclingByScrollDelta(event->y_offset());
     event->SetHandled();
   }
 }
 
 void WorkspaceCycler::StartWorkspaceCyclerAnimationFinished() {
   DCHECK_EQ(STARTING_CYCLING, state_);
   SetState(CYCLING);
 }
 
 void WorkspaceCycler::StopWorkspaceCyclerAnimationFinished() {
   DCHECK_EQ(STOPPING_CYCLING, state_);
   Workspace* workspace_to_activate = animator_->get_selected_workspace();
   animator_.reset();
   SetState(NOT_CYCLING);
 
   // Activate the workspace after updating the state so that a call to
   // AbortCycling() as a result of SetActiveWorkspaceFromCycler() is a noop.
   workspace_manager_->SetActiveWorkspaceFromCycler(workspace_to_activate);
 }
 
 }  // namespace internal
 }  // namespace ash