WindowManagerClient::AddAccelerator() should take an array

ash/mus/accelerators/accelerator_controller_registrar.cc

 // 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.
 
 #include "ash/mus/accelerators/accelerator_controller_registrar.h"
 
 #include <limits>
 
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/common/accelerators/accelerator_router.h"
 #include "ash/common/wm_shell.h"
 #include "ash/mus/accelerators/accelerator_ids.h"
 #include "ash/mus/bridge/wm_window_mus.h"
 #include "ash/mus/window_manager.h"
 #include "base/logging.h"
+#include "services/ui/common/accelerator_transport_util.h"
 #include "services/ui/common/event_matcher_util.h"
 #include "services/ui/public/cpp/window_manager_delegate.h"
 #include "services/ui/public/cpp/window_tree_client.h"
 #include "ui/base/accelerators/accelerator_history.h"
 
 namespace ash {
 namespace mus {
 namespace {
 
 // Callback from registering the accelerator.
@@ skipping 93 matching lines @@
   DCHECK(accelerator.type() == ui::ET_KEY_PRESSED ||
          accelerator.type() == ui::ET_KEY_RELEASED);
   event_matcher->type_matcher->type = accelerator.type() == ui::ET_KEY_PRESSED
                                           ? ui::mojom::EventType::KEY_PRESSED
                                           : ui::mojom::EventType::KEY_RELEASED;
 
   ui::mojom::EventMatcherPtr post_event_matcher = event_matcher.Clone();
   post_event_matcher->accelerator_phase =
       ui::mojom::AcceleratorPhase::POST_TARGET;
 
-  window_manager_->window_manager_client()->AddAccelerator(
-      ComputeAcceleratorId(id_namespace_, ids.pre_id), std::move(event_matcher),
-      base::Bind(OnAcceleratorAdded, accelerator));
-  window_manager_->window_manager_client()->AddAccelerator(
-      ComputeAcceleratorId(id_namespace_, ids.post_id),
-      std::move(post_event_matcher),
+  std::vector<ui::mojom::AcceleratorTransportPtr> pre_accelerators;
+  pre_accelerators =
+      AddAcceleratorHelper(std::move(pre_accelerators),

[mfomitchev, 2016/11/29 01:55:45]

You are never passing a non-empty vector to AddAcceleratorHelper. So perhaps
just make it take id and matcher and return an
std::vector<ui::mojom::AcceleratorTransportPtr>?

If do need to add accelerators to non-empty vector: 
Make AddAcceleratorHelper take a pointer to
std::vector<ui::mojom::AcceleratorTransportPtr> and return nothing and make it
modify the provided std::vector<ui::mojom::AcceleratorTransportPtr>. This way we
don't have to do std::move twice. I find doing std::move a little confusing it
terms of semantics, since we are not actually transferring the ownership.

[thanhph, 2016/11/29 16:50:17]

Done, thanks! I use the first approach since the later didn't work. When I use
std::move to pass std::vector argument to the void 
AddAcceleratorHelper(std::vector<ui::mojom::AcceleratorTransportPtr>, uint32_t
id, ui::mojom::EventMatcherPtr event_matcher), the pointer to std::vector is
gone thus I can't reuse the std::vector on the return function.

+                           ComputeAcceleratorId(id_namespace_, ids.pre_id),
+                           std::move(event_matcher));
+
+  window_manager_->window_manager_client()->AddAccelerators(
+      std::move(pre_accelerators), base::Bind(OnAcceleratorAdded, accelerator));
+
+  std::vector<ui::mojom::AcceleratorTransportPtr> post_accelerators;
+  post_accelerators =
+      AddAcceleratorHelper(std::move(post_accelerators),
+                           ComputeAcceleratorId(id_namespace_, ids.post_id),
+                           std::move(post_event_matcher));
+
+  window_manager_->window_manager_client()->AddAccelerators(
+      std::move(post_accelerators),
       base::Bind(OnAcceleratorAdded, accelerator));
 }
 
 void AcceleratorControllerRegistrar::OnAcceleratorUnregistered(
     const ui::Accelerator& accelerator) {
   auto iter = accelerator_to_ids_.find(accelerator);
   DCHECK(iter != accelerator_to_ids_.end());
   Ids ids = iter->second;
   accelerator_to_ids_.erase(iter);
   ids_.erase(ids.pre_id);
@@ skipping 18 matching lines @@
   // Common case is we never wrap once, so this is typically cheap. Additionally
   // we expect there not to be too many accelerators.
   while (ids_.count(next_id_) > 0)
     ++next_id_;
   ids_.insert(next_id_);
   return next_id_++;
 }
 
 }  // namespace mus
 }  // namespace ash