Inform window manager about modal windows in mus+ash.

services/ui/ws/window_tree.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 "services/ui/ws/window_tree.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 334 matching lines @@
   if (!access_policy_->CanDeleteWindow(window) &&
       !ShouldRouteToWindowManager(window)) {
     return false;
   }
 
   // Have the owner of the tree service the actual delete.
   WindowTree* tree = window_server_->GetTreeWithId(window->id().client_id);
   return tree && tree->DeleteWindowImpl(this, window);
 }
 
-bool WindowTree::SetModalType(const ClientWindowId& window_id,
-                              ModalType modal_type) {
-  ServerWindow* window = GetWindowByClientId(window_id);
+bool WindowTree::SetModalType(ServerWindow* window, ModalType modal_type) {
   if (!window || !access_policy_->CanSetModal(window))
     return false;
 
   if (window->modal_type() == modal_type)
     return true;
 
   // TODO(moshayedi): crbug.com/697176. When modality of a window that used to
   // be a system modal changes, notify window manager state.
   auto* display_root = GetWindowManagerDisplayRoot(window);
   switch (modal_type) {
@@ skipping 920 matching lines @@
                  OperationType::REMOVE_TRANSIENT_WINDOW_FROM_PARENT);
     transient_window->transient_parent()->RemoveTransientWindow(
         transient_window);
   }
   client()->OnChangeCompleted(change_id, success);
 }
 
 void WindowTree::SetModalType(uint32_t change_id,
                               Id window_id,
                               ModalType modal_type) {
-  client()->OnChangeCompleted(
-      change_id, SetModalType(ClientWindowId(window_id), modal_type));
+  ServerWindow* window = GetWindowByClientId(ClientWindowId(window_id));
+  if (window && ShouldRouteToWindowManager(window)) {
+    WindowTree* wm_tree = GetWindowManagerDisplayRoot(window)

[sky, 2017/03/14 21:16:22]

As ash always allows the change I suggest you forward the change to ash, but
don't require a return value.

[Hadi, 2017/03/17 16:16:32]

Done. I also moved the forwarding part to the other overload of SetModalType()
so I can test forwarding in window_tree_unittest.

+                              ->window_manager_state()
+                              ->window_tree();
+    wm_tree->window_manager_internal_->WmSetModalType(
+        window_server_->GenerateWindowManagerChangeId(this, change_id),

[sky, 2017/03/14 21:16:23]

If you generate a change id like this the expectation is that the window manager
would ack the change id. You don't have that here. Follow the pattern used in
SetCanFocus.

[Hadi, 2017/03/17 16:16:32]

Done.

+        wm_tree->ClientWindowIdForWindow(window).id, modal_type);
+    return;
+  }
+  client()->OnChangeCompleted(change_id, SetModalType(window, modal_type));
 }
 
 void WindowTree::ReorderWindow(uint32_t change_id,
                                Id window_id,
                                Id relative_window_id,
                                mojom::OrderDirection direction) {
   // TODO(erg): This implementation allows reordering two windows that are
   // children of a parent window which the two implementations can't see. There
   // should be a security check to prevent this.
   bool success = false;
@@ skipping 869 matching lines @@
   client()->OnCompleteDrop(client_window_id.id, event_flags, cursor_offset,
                            effect_bitmask, callback);
 }
 
 void WindowTree::PerformOnDragDropDone() {
   client()->OnDragDropDone();
 }
 
 }  // namespace ws
 }  // namespace ui