Add EventTargeterDelegate for EventTargeter in mus-ws.

Right now EventTargeter talks to EventDispatcherDelegate directly but it
should not have any knowledge of EventDispatcherDelegate. Adding an
EventTargeterDelegate to route calls to EventDispatcher and then
EventDispatcherDelegate.

BUG=none, related to https://codereview.chromium.org/2905333002/
TEST=covered by tests

Review-Url: https://codereview.chromium.org/2911293002
Cr-Commit-Position: refs/heads/master@{#476483}

services/ui/ws/BUILD.gn

@@ -48,6 +48,7 @@ static_library("lib") {
     "event_matcher.h",
     "event_targeter.cc",
     "event_targeter.h",
+    "event_targeter_delegate.h",
     "focus_controller.cc",
     "focus_controller.h",
     "focus_controller_delegate.h",

services/ui/ws/event_dispatcher.cc

@@ -47,8 +47,7 @@ EventDispatcher::EventDispatcher(EventDispatcherDelegate* delegate)
       capture_window_client_id_(kInvalidClientId),
       modal_window_controller_(this),
       event_targeter_(
-          base::MakeUnique<EventTargeter>(delegate_,
-                                          &modal_window_controller_)),
+          base::MakeUnique<EventTargeter>(this, &modal_window_controller_)),
       mouse_button_down_(false),
       mouse_cursor_source_window_(nullptr),
       mouse_cursor_in_non_client_area_(false) {}
@@ -317,6 +316,12 @@ void EventDispatcher::ProcessEvent(const ui::Event& event,
   return;
 }
 
+ServerWindow* EventDispatcher::GetRootWindowContaining(
+    gfx::Point* location_in_display,
+    int64_t* display_id) {
+  return delegate_->GetRootWindowContaining(location_in_display, display_id);
+}
+
 void EventDispatcher::SetMouseCursorSourceWindow(ServerWindow* window) {
   if (mouse_cursor_source_window_ == window)
     return;

services/ui/ws/event_dispatcher.h

@@ -17,6 +17,7 @@
 #include "services/ui/public/interfaces/window_manager.mojom.h"
 #include "services/ui/ws/drag_cursor_updater.h"
 #include "services/ui/ws/event_targeter.h"
+#include "services/ui/ws/event_targeter_delegate.h"
 #include "services/ui/ws/modal_window_controller.h"
 #include "services/ui/ws/server_window_observer.h"
 #include "ui/gfx/geometry/rect_f.h"
@@ -41,7 +42,9 @@ class EventDispatcherTestApi;
 }
 
 // Handles dispatching events to the right location as well as updating focus.
-class EventDispatcher : public ServerWindowObserver, public DragCursorUpdater {
+class EventDispatcher : public ServerWindowObserver,
+                        public DragCursorUpdater,
+                        public EventTargeterDelegate {
  public:
   enum class AcceleratorMatchPhase {
     // Both pre and post should be considered.
@@ -148,6 +151,10 @@ class EventDispatcher : public ServerWindowObserver, public DragCursorUpdater {
                     const int64_t display_id,
                     AcceleratorMatchPhase match_phase);
 
+  // EventTargeterDelegate:
+  ServerWindow* GetRootWindowContaining(gfx::Point* location_in_display,
+                                        int64_t* display_id) override;
+
  private:
   friend class test::EventDispatcherTestApi;
 

services/ui/ws/event_targeter.cc

@@ -4,7 +4,7 @@
 
 #include "services/ui/ws/event_targeter.h"
 
-#include "services/ui/ws/event_dispatcher_delegate.h"
+#include "services/ui/ws/event_targeter_delegate.h"
 #include "services/ui/ws/modal_window_controller.h"
 #include "services/ui/ws/window_finder.h"
 #include "ui/events/event.h"
@@ -13,9 +13,9 @@
 namespace ui {
 namespace ws {
 
-EventTargeter::EventTargeter(EventDispatcherDelegate* event_dispatcher_delegate,
+EventTargeter::EventTargeter(EventTargeterDelegate* event_targeter_delegate,
                              ModalWindowController* modal_window_controller)
-    : event_dispatcher_delegate_(event_dispatcher_delegate),
+    : event_targeter_delegate_(event_targeter_delegate),
       modal_window_controller_(modal_window_controller) {}
 
 EventTargeter::~EventTargeter() {}
@@ -41,7 +41,7 @@ DeepestWindow EventTargeter::FindDeepestVisibleWindowForEvents(
     gfx::Point* location,
     int64_t* display_id) {
   ServerWindow* root =
-      event_dispatcher_delegate_->GetRootWindowContaining(location, display_id);
+      event_targeter_delegate_->GetRootWindowContaining(location, display_id);
   return root ? ui::ws::FindDeepestVisibleWindowForEvents(root, *location)
               : DeepestWindow();
 }

services/ui/ws/event_targeter.h

@@ -18,7 +18,7 @@ class LocatedEvent;
 
 namespace ws {
 struct DeepestWindow;
-class EventDispatcherDelegate;
+class EventTargeterDelegate;
 class ModalWindowController;
 class ServerWindow;
 
@@ -46,7 +46,7 @@ struct PointerTarget {
 // Finds the PointerTarget for an event or the DeepestWindow for a location.
 class EventTargeter {
  public:
-  EventTargeter(EventDispatcherDelegate* event_dispatcher_delegate,
+  EventTargeter(EventTargeterDelegate* event_targeter_delegate,
                 ModalWindowController* modal_window_controller);
   ~EventTargeter();
 
@@ -62,7 +62,7 @@ class EventTargeter {
                                                   int64_t* display_id);
 
  private:
-  EventDispatcherDelegate* event_dispatcher_delegate_;
+  EventTargeterDelegate* event_targeter_delegate_;
   ModalWindowController* modal_window_controller_;
 
   DISALLOW_COPY_AND_ASSIGN(EventTargeter);

services/ui/ws/event_targeter_delegate.h

+// Copyright 2017 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 SERVICES_UI_WS_EVENT_TARGETER_DELEGATE_H_
+#define SERVICES_UI_WS_EVENT_TARGETER_DELEGATE_H_
+
+#include <stdint.h>
+
+namespace gfx {
+class Point;
+}
+
+namespace ui {
+namespace ws {
+class ServerWindow;
+
+// Used by EventTargeter to talk to WindowManagerState.
+class EventTargeterDelegate {
+ public:
+  // Calls EventDispatcherDelegate::GetRootWindowContaining, see
+  // event_dispatcher_delegate.h for details.
+  virtual ServerWindow* GetRootWindowContaining(gfx::Point* location_in_display,
+                                                int64_t* display_id) = 0;
+
+ protected:
+  virtual ~EventTargeterDelegate() {}
+};
+
+}  // namespace ws
+}  // namespace ui
+
+#endif  // SERVICES_UI_WS_EVENT_TARGETER_DELEGATE_H_