Adds ability for pre-target accelerators to not consume events

services/ui/ws/window_manager_state.h

 // Copyright 2016 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_WINDOW_MANAGER_STATE_H_
 #define SERVICES_UI_WS_WINDOW_MANAGER_STATE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 61 matching lines @@
   void Deactivate();
 
   // Processes an event from PlatformDisplay.
   void ProcessEvent(const ui::Event& event);
 
   // Called when the ack from an event dispatched to WindowTree |tree| is
   // received.
   // TODO(sky): make this private and use a callback.
   void OnEventAck(mojom::WindowTree* tree, mojom::EventResult result);
 
+  // Called when the WindowManager acks an accelerator.
+  void OnAcceleratorAck(mojom::EventResult result);
+
  private:
   class ProcessedEventTarget;
   friend class Display;
   friend class test::WindowManagerStateTestApi;
 
+  enum class EventDispatchPhase {
+    // Not actively dispatching.
+    NONE,
+
+    // A PRE_TARGET accelerator has been encountered and we're awaiting the ack.
+    PRE_TARGET_ACCELERATOR,
+
+    // Dispatching to the target, awaiting the ack.
+    TARGET,
+  };
+
   // There are two types of events that may be queued, both occur only when
   // waiting for an ack from a client.
   // . We get an event from the PlatformDisplay. This results in |event| being
   //   set, but |processed_target| is null.
   // . We get an event from the EventDispatcher. In this case both |event| and
   //   |processed_target| are valid.
   // The second case happens if EventDispatcher generates more than one event
   // at a time.
   struct QueuedEvent {
     QueuedEvent();
     ~QueuedEvent();
 
     std::unique_ptr<ui::Event> event;
     std::unique_ptr<ProcessedEventTarget> processed_target;
   };
 
   const WindowServer* window_server() const;
   WindowServer* window_server();
 
   DisplayManager* display_manager();
   const DisplayManager* display_manager() const;
 
   // Sets the visibility of all window manager roots windows to |value|.
   void SetAllRootWindowsVisible(bool value);
 
   // Returns the ServerWindow that is the root of the WindowManager for
   // |window|. |window| corresponds to the root of a Display.
   ServerWindow* GetWindowManagerRoot(ServerWindow* window);
 
+  // Called if the client doesn't ack an event in the appropriate amount of
+  // time.
   void OnEventAckTimeout(ClientSpecificId client_id);
 
   // Schedules an event to be processed later.
   void QueueEvent(const ui::Event& event,
                   std::unique_ptr<ProcessedEventTarget> processed_event_target);
 
   // Processes the next valid event in |event_queue_|. If the event has already
   // been processed it is dispatched, otherwise the event is passed to the
   // EventDispatcher for processing.
   void ProcessNextEventFromQueue();
 
   // Dispatches the event to the appropriate client and starts the ack timer.
   void DispatchInputEventToWindowImpl(ServerWindow* target,
                                       ClientSpecificId client_id,
                                       const ui::Event& event,
                                       base::WeakPtr<Accelerator> accelerator);
 
   // Registers accelerators used internally for debugging.
   void AddDebugAccelerators();
 
   // Returns true if the accelerator was handled.
   bool HandleDebugAccelerator(uint32_t accelerator_id);
 
+  // Called when waiting for an event or accelerator to be processed by |tree|.
+  void ScheduleInputEventTimeout(WindowTree* tree);
+
   // EventDispatcherDelegate:
-  void OnAccelerator(uint32_t accelerator_id, const ui::Event& event) override;
+  void OnAccelerator(uint32_t accelerator_id,
+                     const ui::Event& event,
+                     AcceleratorPhase phase) override;
   void SetFocusedWindowFromEventDispatcher(ServerWindow* window) override;
   ServerWindow* GetFocusedWindowForEventDispatcher() override;
   void SetNativeCapture(ServerWindow* window) override;
   void ReleaseNativeCapture() override;
   void OnServerWindowCaptureLost(ServerWindow* window) override;
   void OnMouseCursorLocationChanged(const gfx::Point& point) override;
   void DispatchInputEventToWindow(ServerWindow* target,
                                   ClientSpecificId client_id,
                                   const ui::Event& event,
                                   Accelerator* accelerator) override;
   ClientSpecificId GetEventTargetClientId(const ServerWindow* window,
                                           bool in_nonclient_area) override;
   ServerWindow* GetRootWindowContaining(const gfx::Point& location) override;
   void OnEventTargetNotFound(const ui::Event& event) override;
 
   // The single WindowTree this WindowManagerState is associated with.
   // |window_tree_| owns this.
   WindowTree* window_tree_;
 
   // Set to true the first time SetFrameDecorationValues() is called.
   bool got_frame_decoration_values_ = false;
   mojom::FrameDecorationValuesPtr frame_decoration_values_;
 
+  EventDispatchPhase event_dispatch_phase_ = EventDispatchPhase::NONE;
+  // The tree we're waiting to process the current accelerator or event.
   mojom::WindowTree* tree_awaiting_input_ack_ = nullptr;
+  // The event we're awaiting an accelerator or input ack from.
   std::unique_ptr<ui::Event> event_awaiting_input_ack_;
   base::WeakPtr<Accelerator> post_target_accelerator_;
   std::queue<std::unique_ptr<QueuedEvent>> event_queue_;
   base::OneShotTimer event_ack_timer_;
 
   EventDispatcher event_dispatcher_;
 
   // PlatformDisplay that currently has capture.
   PlatformDisplay* platform_display_with_capture_ = nullptr;
 
   base::WeakPtrFactory<WindowManagerState> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowManagerState);
 };
 
 }  // namespace ws
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_WINDOW_MANAGER_STATE_H_