Add an adapter layer (WMHelper) between exo and ash.

components/exo/pointer.cc

 // 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 "components/exo/pointer.h"
 
 #include "ash/common/display/display_info.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/display/display_manager.h"
-#include "ash/shell.h"
 #include "components/exo/pointer_delegate.h"
 #include "components/exo/pointer_stylus_delegate.h"
 #include "components/exo/surface.h"
+#include "components/exo/wm_helper.h"
+#include "ui/aura/client/cursor_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
+#include "ui/display/screen.h"
 #include "ui/events/event.h"
 #include "ui/gfx/geometry/vector2d_conversions.h"
 #include "ui/views/widget/widget.h"
 
 namespace exo {
 namespace {
 
 static constexpr float kLargeCursorScale = 2.8;
 
 // Synthesized events typically lack floating point precision so to avoid
 // generating mouse event jitter we consider the location of these events
 // to be the same as |location| if floored values match.
 bool SameLocation(const ui::LocatedEvent* event, const gfx::PointF& location) {
   if (event->flags() & ui::EF_IS_SYNTHESIZED)
     return event->location() == gfx::ToFlooredPoint(location);
 
   return event->location_f() == location;
 }
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // Pointer, public:
 
 Pointer::Pointer(PointerDelegate* delegate)
     : delegate_(delegate),
       surface_(nullptr),
       focus_(nullptr),
       cursor_scale_(1.0f) {
-  ash::Shell* ash_shell = ash::Shell::GetInstance();
-  ash_shell->AddPreTargetHandler(this);
-
-  wm::CursorManager* cursor_manager = ash_shell->cursor_manager();
-  DCHECK(cursor_manager);
-  cursor_manager->AddObserver(this);
+  auto* helper = WMHelper::GetInstance();
+  helper->AddPreTargetHandler(this);
+  helper->AddCursorObserver(this);
 }
 
 Pointer::~Pointer() {
   delegate_->OnPointerDestroying(this);
   if (stylus_delegate_)
     stylus_delegate_->OnPointerDestroying(this);
   if (surface_)
     surface_->RemoveSurfaceObserver(this);
   if (focus_) {
     focus_->RemoveSurfaceObserver(this);
     focus_->UnregisterCursorProvider(this);
   }
   if (widget_)
     widget_->CloseNow();
 
-  ash::Shell* ash_shell = ash::Shell::GetInstance();
-  DCHECK(ash_shell->cursor_manager());
-  ash_shell->cursor_manager()->RemoveObserver(this);
-  ash_shell->RemovePreTargetHandler(this);
+  auto* helper = WMHelper::GetInstance();
+  helper->RemoveCursorObserver(this);
+  helper->RemovePreTargetHandler(this);
 }
 
 void Pointer::SetCursor(Surface* surface, const gfx::Point& hotspot) {
   // Early out if the pointer doesn't have a surface in focus.
   if (!focus_)
     return;
 
   // If surface is different than the current pointer surface then remove the
   // current surface and add the new surface.
   if (surface != surface_) {
@@ skipping 235 matching lines @@
 void Pointer::CreatePointerWidget() {
   DCHECK(!widget_);
 
   views::Widget::InitParams params;
   params.type = views::Widget::InitParams::TYPE_TOOLTIP;
   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
   params.shadow_type = views::Widget::InitParams::SHADOW_TYPE_NONE;
   params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
   params.accept_events = false;
   params.parent =
-      ash::Shell::GetContainer(ash::Shell::GetPrimaryRootWindow(),
-                               ash::kShellWindowId_MouseCursorContainer);
+      WMHelper::GetContainer(ash::kShellWindowId_MouseCursorContainer);
   widget_.reset(new views::Widget);
   widget_->Init(params);
   widget_->GetNativeWindow()->set_owned_by_parent(false);
   widget_->GetNativeWindow()->SetName("ExoPointer");
 }
 
 Surface* Pointer::GetEffectiveTargetForEvent(ui::Event* event) const {
   Surface* target =
       Surface::AsSurface(static_cast<aura::Window*>(event->target()));
   if (!target)
     return nullptr;
 
   return delegate_->CanAcceptPointerEventsForSurface(target) ? target : nullptr;
 }
 
 void Pointer::UpdateCursorScale() {
   if (!focus_)
     return;
 
   // Update cursor scale if the effective UI scale has changed.
   display::Display display =
       display::Screen::GetScreen()->GetDisplayNearestWindow(
           widget_->GetNativeWindow());
-  float ui_scale = ash::Shell::GetInstance()
-                       ->display_manager()
+  float ui_scale = WMHelper::GetInstance()
                        ->GetDisplayInfo(display.id())
                        .GetEffectiveUIScale();
-
-  ash::Shell* ash_shell = ash::Shell::GetInstance();
-  if (ash_shell->cursor_manager()->GetCursorSet() == ui::CURSOR_SET_LARGE)
+  if (WMHelper::GetInstance()->GetCursorSet() == ui::CURSOR_SET_LARGE)
     ui_scale *= kLargeCursorScale;
 
   if (ui_scale != cursor_scale_) {
     gfx::Transform transform;
     transform.Scale(ui_scale, ui_scale);
     widget_->GetNativeWindow()->SetTransform(transform);
     cursor_scale_ = ui_scale;
   }
 }
 
 }  // namespace exo