Make mash register initial batch of accelerators in single shot.

ash/mus/accelerators/accelerator_controller_registrar.cc

Index: ash/mus/accelerators/accelerator_controller_registrar.cc
diff --git a/ash/mus/accelerators/accelerator_controller_registrar.cc b/ash/mus/accelerators/accelerator_controller_registrar.cc
index 12df77c21a1df982aeb715dc7226fcf2f54ea6eb..895973acb54d2116def46055bc679c770919e622 100644
--- a/ash/mus/accelerators/accelerator_controller_registrar.cc
+++ b/ash/mus/accelerators/accelerator_controller_registrar.cc
@@ -28,7 +28,14 @@ void OnAcceleratorAdded(const ui::Accelerator& accelerator, bool added) {
                 << " modifiers=" << accelerator.modifiers();
 }
 
+// Callback from registering the accelerators.
+void OnAcceleratorsAdded(const std::vector<ui::Accelerator>& ui_accelerators,
+                         bool added) {
+  for (auto iter = ui_accelerators.begin(); iter != ui_accelerators.end();
+       ++iter)
+    OnAcceleratorAdded(*iter, added);
 }  // namespace
+}
 
 AcceleratorControllerRegistrar::AcceleratorControllerRegistrar(
     WindowManager* window_manager,
@@ -99,8 +106,21 @@ ui::mojom::EventResult AcceleratorControllerRegistrar::OnAccelerator(
              : ui::mojom::EventResult::UNHANDLED;
 }
 
+void AcceleratorControllerRegistrar::OnAcceleratorsRegistered(
+    const std::vector<ui::Accelerator>& accelerators) {
+  accelerator_ptrs_.clear();

[mfomitchev, 2016/12/22 01:04:50]

I think this all could be done a bit cleaner:
Don't make |accelerator_ptrs_| into a class member. It can just be a local
variable. Add a function:
AddAcceleratorToVector(const ui::Accelerator& accelerator, const
std::vector<ui::mojom::AcceleratorPtr>& accelerator_vector)

Call this function from OnAcceleratorsAdded repeatedly passing it the vector
(which can be a local variable).

Also call this function from OnAcceleratorRegistered, passing it the empty
vector. Get rid of |add_accelerator_immediately|.

[thanhph, 2016/12/22 17:48:44]

If we get rid of |add_accelerator_immediately|, we can't distinguish function
call between OnAcceleratorRegistered and OnAcceleratorsRegistered. This means we
need to call window_manager_->window_manager_client()->AddAccelerators() each
time the function OnAcceleratorRegistered() ends to register 1 accelerator with
1 IPC. Since OnAcceleratorsRegistered() will call OnAcceleratorRegistered(),
ideally we only need one IPC call for adding entire accelerators in accelerator
vector, which |add_accelerator_immediately| will serve this purpose.

+  for (auto iter = accelerators.begin(); iter != accelerators.end(); ++iter)
+    OnAcceleratorRegistered(*iter, false);
+
+  window_manager_->window_manager_client()->AddAccelerators(
+      std::move(accelerator_ptrs_),
+      base::Bind(OnAcceleratorsAdded, accelerators));
+}
+
+// add_accelerator_immediately default set to true.
 void AcceleratorControllerRegistrar::OnAcceleratorRegistered(
-    const ui::Accelerator& accelerator) {
+    const ui::Accelerator& accelerator,
+    bool add_accelerator_immediately) {
   Ids ids;
   if (!GenerateIds(&ids)) {
     DVLOG(1) << "max number of accelerators registered, dropping request";
@@ -124,17 +144,26 @@ void AcceleratorControllerRegistrar::OnAcceleratorRegistered(
   post_event_matcher->accelerator_phase =
       ui::mojom::AcceleratorPhase::POST_TARGET;
 
-  window_manager_->window_manager_client()->AddAccelerators(
-      ui::CreateAcceleratorVector(
-          ComputeAcceleratorId(id_namespace_, ids.pre_id),
-          std::move(event_matcher)),
-      base::Bind(OnAcceleratorAdded, accelerator));
-
-  window_manager_->window_manager_client()->AddAccelerators(
-      ui::CreateAcceleratorVector(
-          ComputeAcceleratorId(id_namespace_, ids.post_id),
-          std::move(post_event_matcher)),
-      base::Bind(OnAcceleratorAdded, accelerator));
+  if (add_accelerator_immediately) {
+    window_manager_->window_manager_client()->AddAccelerators(

[mfomitchev, 2016/12/22 01:04:50]

Can we create an array vector the accelerators we are adding here and add that?
This way we'd be doing one IPC instead of two.

[thanhph, 2016/12/22 20:36:01]

Done.

+        ui::CreateAcceleratorVector(
+            ComputeAcceleratorId(id_namespace_, ids.pre_id),
+            std::move(event_matcher)),
+        base::Bind(OnAcceleratorAdded, accelerator));
+
+    window_manager_->window_manager_client()->AddAccelerators(
+        ui::CreateAcceleratorVector(
+            ComputeAcceleratorId(id_namespace_, ids.post_id),
+            std::move(post_event_matcher)),
+        base::Bind(OnAcceleratorAdded, accelerator));
+  } else {
+    accelerator_ptrs_.push_back(
+        ui::CreateAccelerator(ComputeAcceleratorId(id_namespace_, ids.pre_id),
+                              std::move(event_matcher)));
+    accelerator_ptrs_.push_back(
+        ui::CreateAccelerator(ComputeAcceleratorId(id_namespace_, ids.post_id),
+                              std::move(post_event_matcher)));
+  }
 }
 
 void AcceleratorControllerRegistrar::OnAcceleratorUnregistered(
@@ -152,6 +181,13 @@ void AcceleratorControllerRegistrar::OnAcceleratorUnregistered(
       ComputeAcceleratorId(id_namespace_, ids.post_id));
 }
 
+void AcceleratorControllerRegistrar::OnAcceleratorsUnregistered(
+    std::vector<ui::Accelerator>& accelerators) {
+  for (auto iter = accelerators.begin(); iter != accelerators.end(); ++iter) {
+    OnAcceleratorUnregistered(*iter);
+  }
+}
+
 bool AcceleratorControllerRegistrar::GenerateIds(Ids* ids) {
   if (ids_.size() + 2 >= std::numeric_limits<uint16_t>::max())
     return false;