mus: Let clients set the cursor of their window.

components/mus/public/cpp/lib/window_tree_client_impl.cc

 // 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.
 
 #include "components/mus/public/cpp/lib/window_tree_client_impl.h"
 
 #include "base/bind.h"
 #include "components/mus/common/util.h"
 #include "components/mus/public/cpp/lib/in_flight_change.h"
 #include "components/mus/public/cpp/lib/window_private.h"
@@ skipping 204 matching lines @@
   // we got a connection.
   DCHECK(tree_);
   tree_->SetFocus(window_id);
 }
 
 void WindowTreeClientImpl::SetCanFocus(Id window_id, bool can_focus) {
   DCHECK(tree_);
   tree_->SetCanFocus(window_id, can_focus);
 }
 
+void WindowTreeClientImpl::SetPredefinedCursor(Id window_id,
+                                               mus::mojom::Cursor cursor_id) {
+  DCHECK(tree_);
+
+  Window* window = GetWindowById(window_id);
+  if (!window)
+    return;
+
+  // We make an inflight change thing here.
+  const uint32_t change_id = ScheduleInFlightChange(make_scoped_ptr(
+      new InFlightPredefinedCursorChange(window, window->predefined_cursor())));
+  tree_->SetPredefinedCursor(change_id, window_id, cursor_id);
+}
+
 void WindowTreeClientImpl::SetVisible(Window* window, bool visible) {
   DCHECK(tree_);
   const uint32_t change_id = ScheduleInFlightChange(
       make_scoped_ptr(new InFlightVisibleChange(window, !visible)));
   tree_->SetWindowVisibility(change_id, window->id(), visible);
 }
 
 void WindowTreeClientImpl::SetProperty(Window* window,
                                        const std::string& name,
                                        mojo::Array<uint8_t> data) {
@@ skipping 355 matching lines @@
   if (blurred) {
     FOR_EACH_OBSERVER(WindowObserver, *WindowPrivate(blurred).observers(),
                       OnWindowFocusChanged(focused, blurred));
   }
   if (focused) {
     FOR_EACH_OBSERVER(WindowObserver, *WindowPrivate(focused).observers(),
                       OnWindowFocusChanged(focused, blurred));
   }
 }
 
+void WindowTreeClientImpl::OnWindowPredefinedCursorChanged(
+    Id window_id,
+    mojom::Cursor cursor) {
+  Window* window = GetWindowById(window_id);
+  if (window) {
+    FOR_EACH_OBSERVER(WindowObserver, *WindowPrivate(window).observers(),

[sky, 2015/12/03 22:01:10]

You need two things here:
1. If there is an in flight cursor change, you need to merge with it. See
OnWindowBoundsChanged for an example of what I mean.
2. Potentially set the cursor value locally. Again, follow the modle of
OnWindowBoundsChanged.

[Elliot Glaysher, 2015/12/03 22:32:00]

Done. (I think.)

+                      OnWindowPredefinedCursorChanged(window, cursor));
+  }
+}
+
 void WindowTreeClientImpl::OnChangeCompleted(uint32 change_id, bool success) {
   scoped_ptr<InFlightChange> change(std::move(in_flight_map_[change_id]));
   in_flight_map_.erase(change_id);
   if (!change)
     return;
 
   if (!success)
     change->ChangeFailed();
 
   InFlightChange* next_change = GetOldestInFlightChangeMatching(*change);
@@ skipping 48 matching lines @@
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // WindowTreeClientImpl, private:
 
 mojo::Callback<void(bool)> WindowTreeClientImpl::ActionCompletedCallback() {
   return [this](bool success) {};
 }
 
 }  // namespace mus