Updates PointerEventRouter to handle switching move type

services/ui/public/interfaces/window_tree.mojom

 // 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.
 
 module ui.mojom;
 
 import "cc/ipc/surface_id.mojom";
 import "services/ui/public/interfaces/cursor.mojom";
 import "services/ui/public/interfaces/event_matcher.mojom";
 import "services/ui/public/interfaces/mus_constants.mojom";
@@ skipping 69 matching lines @@
   // Releases input event capture for the given |window_id|. This does nothing
   // if |window_id| does not currently have capture.
   ReleaseCapture(uint32 change_id, uint32 window_id);
 
   // Starts the pointer watcher that monitors pointer events (up/down events if
   // |wants_moves| is false, up/down and move if |wants_moves| is true), even if
   // they are not targeted at a window in this tree. For pointer events that
   // would normally be sent to the requesting client (if the event target is
   // this window tree) OnWindowInputEvent() is called, all other matching
   // pointer events (if the target is another tree) result in
-  // OnPointerEventObserved(). The client must supply a non-zero
-  // |pointer_watcher_id|, which is reported back with matched events. There is
-  // only ever one pointer watcher active at a given time. The client should
-  // prefer |want_moves| to be false, as there's a system-wide performance/
-  // battery penalty for listening to moves.
+  // OnPointerEventObserved(). There is only ever one pointer watcher active at
+  // a given time. The client should prefer |want_moves| to be false, as there's
+  // a system-wide performance/ battery penalty for listening to moves.

[msw, 2016/08/18 22:45:23]

nit: no space after slash

[sky, 2016/08/18 23:17:14]

Done.

   //
   // See class description for details on event delivery.
-  StartPointerWatcher(bool want_moves, uint32 pointer_watcher_id);
+  StartPointerWatcher(bool want_moves);
 
   // Stops the pointer watcher for all events.
   StopPointerWatcher();
 
   // Sets the specified bounds of the specified window.
   SetWindowBounds(uint32 change_id, uint32 window_id, gfx.mojom.Rect bounds);
 
   // Sets the client area of the specified window. The client area is specified
   // by way of insets. Everything outside of the insets, and not in
   // |additional_client_areas| is considered non-client area.
@@ skipping 261 matching lines @@
 
   // Invoked when a window property is changed. If this change is a removal,
   // |new_data| is null.
   OnWindowSharedPropertyChanged(uint32 window,
                                 string name,
                                 array<uint8>? new_data);
 
   // Invoked when an event is targeted at the specified window. The client must
   // call WindowTree::OnWindowInputEventAck() with the same |event_id| to notify
   // that the event has been processed, and with an EventResult value to notify
-  // if the event was consumed. |pointer_watcher_id| is the id supplied to
-  // StartPointerWatcher() if the event is a pointer event and the client called
-  // StartPointerWatcher(). The client will not receive farther events until the
-  // event is ack'ed.
+  // if the event was consumed. |matches_pointer_watcher| is true if the client
+  // has called StartPointerWatcher() and the event matches the type of events
+  // specified by StartPointerWatcher(). The client will not receive farther
+  // events until the event is ack'ed.

[msw, 2016/08/18 22:45:23]

optional nit: clarify if pointer watcher events should be acked?

[sky, 2016/08/18 23:17:14]

Done.

   OnWindowInputEvent(uint32 event_id,
                      uint32 window,
                      ui.mojom.Event event,
-                     uint32 pointer_watcher_id);
+                     bool matches_pointer_watcher);
 
   // Called when a pointer event that would not normally be targeted at this

[msw, 2016/08/18 22:45:23]

aside q: Could we fold this into OnWindowInputEvent? (separately, if at all)

[sky, 2016/08/18 23:17:14]

We certainly could, but in some ways it's nice to have the two as one requires a
response and one doesn't. I'm going to keep it like this for now.

-  // client is encountered and the client called StartPointerWatcher(). The
-  // |pointer_watcher_id| is the one supplied to StartPointerWatcher(). See
+  // client is encountered and the client called StartPointerWatcher(). See
   // StartPointerWatcher() for details. |window_id| is the window id of the
   // event target, or 0 if the window is not known to this client. The
   // client should not acknowledge these events.
-  OnPointerEventObserved(ui.mojom.Event event,
-                         uint32 pointer_watcher_id,
-                         uint32 window_id);
+  OnPointerEventObserved(ui.mojom.Event event, uint32 window_id);
 
   // Called in two distinct cases: when a window known to the connection gains
   // focus, or when focus moves from a window known to the connection to a
   // window not known to the connection. In the later case |focused_window_id|
   // is 0. As with other functions this is only called if the client did not
   // initiate the change.
   OnWindowFocused(uint32 focused_window_id);
 
   OnWindowPredefinedCursorChanged(uint32 window_id, Cursor cursor_id);
 
   // A change initiated from the client has completed. See description of
   // change ids for details.
   OnChangeCompleted(uint32 change_id, bool success);
 
   // The WindowManager is requesting the specified window to close. If the
   // client allows the change it should delete the window.
   RequestClose(uint32 window_id);
 
   // See description of WindowManager for details.
   GetWindowManager(associated WindowManager& internal);
 };
 
 // Mus provides this interface as a way for clients to connect and obtain a
 // WindowTree handle with a supplied WindowTreeClient handle. The
 // WindowTreeClient has no roots, use NewTopLevelWindow() to create one.
 interface WindowTreeFactory {
   CreateWindowTree(WindowTree& tree_request, WindowTreeClient client);
 };