Add Mojo IPC based input-device service.

components/mus/input_devices/input_device_server.cc

Index: components/mus/input_devices/input_device_server.cc
diff --git a/components/mus/input_devices/input_device_server.cc b/components/mus/input_devices/input_device_server.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3d201f50543294fd1059e5af7f4775563281d469
--- /dev/null
+++ b/components/mus/input_devices/input_device_server.cc
@@ -0,0 +1,112 @@
+// 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 "components/mus/input_devices/input_device_server.h"
+
+#include <utility>
+#include <vector>
+
+#include "mojo/public/cpp/bindings/array.h"
+#include "ui/events/devices/input_device.h"
+#include "ui/events/devices/touchscreen_device.h"
+
+namespace input_device {
+
+InputDeviceServer::InputDeviceServer() {}
+
+InputDeviceServer::~InputDeviceServer() {
+  if (manager_ && ui::DeviceDataManager::HasInstance()) {
+    manager_->RemoveObserver(this);
+    manager_ = nullptr;
+  }
+}
+
+void InputDeviceServer::RegisterAsObserver() {
+  if (!manager_) {
+    manager_ = ui::DeviceDataManager::GetInstance();
+    manager_->AddObserver(this);
+  }
+}
+
+void InputDeviceServer::RegisterInterface(shell::Connection* connection) {
+  DCHECK(manager_);
+  connection->AddInterface<mojom::InputDeviceServer>(this);
+}
+
+void InputDeviceServer::Create(shell::Connection* connection,

[sadrul, 2016/06/10 18:01:49]

This should be at the end (order in .h should match order in .cc)

[kylechar, 2016/06/10 19:29:31]

Done.

+                               mojom::InputDeviceServerRequest request) {
+  bindings_.AddBinding(this, std::move(request));
+}
+
+void InputDeviceServer::AddObserver(
+    mojom::InputDeviceObserverMojoPtr observer) {
+  // We only want to send this message once, so we need to check to make sure
+  // device lists are actually complete before sending it to a new observer.
+  if (manager_->AreDeviceListsComplete())
+    SendDeviceListsComplete(observer.get());
+  observers_.AddPtr(std::move(observer));
+}
+
+void InputDeviceServer::OnKeyboardDeviceConfigurationChanged() {
+  if (manager_->AreDeviceListsComplete()) {

[sadrul, 2016/06/10 18:01:49]

Early return if not-complete instead in these functions.

[kylechar, 2016/06/10 19:29:31]

Done.

+    auto& devices = manager_->GetKeyboardDevices();
+    observers_.ForAllPtrs([&devices](mojom::InputDeviceObserverMojo* observer) {
+      observer->OnKeyboardDeviceConfigurationChanged(
+          mojo::Array<ui::InputDevice>::From(devices));
+    });
+  }
+}
+
+void InputDeviceServer::OnTouchscreenDeviceConfigurationChanged() {
+  if (manager_->AreDeviceListsComplete()) {
+    auto& devices = manager_->GetTouchscreenDevices();
+    observers_.ForAllPtrs([&devices](mojom::InputDeviceObserverMojo* observer) {
+      observer->OnTouchscreenDeviceConfigurationChanged(
+          mojo::Array<ui::TouchscreenDevice>::From(devices));
+    });
+  }
+}
+
+void InputDeviceServer::OnMouseDeviceConfigurationChanged() {
+  if (manager_->AreDeviceListsComplete()) {
+    auto& devices = manager_->GetMouseDevices();
+    observers_.ForAllPtrs([&devices](mojom::InputDeviceObserverMojo* observer) {
+      observer->OnMouseDeviceConfigurationChanged(
+          mojo::Array<ui::InputDevice>::From(devices));
+    });
+  }
+}
+
+void InputDeviceServer::OnTouchpadDeviceConfigurationChanged() {
+  if (manager_->AreDeviceListsComplete()) {
+    auto& devices = manager_->GetTouchpadDevices();
+    observers_.ForAllPtrs([&devices](mojom::InputDeviceObserverMojo* observer) {
+      observer->OnTouchpadDeviceConfigurationChanged(
+          mojo::Array<ui::InputDevice>::From(devices));
+    });
+  }
+}
+
+void InputDeviceServer::OnDeviceListsComplete() {
+  observers_.ForAllPtrs([this](mojom::InputDeviceObserverMojo* observer) {
+    SendDeviceListsComplete(observer);
+  });
+}
+
+void InputDeviceServer::SendDeviceListsComplete(
+    mojom::InputDeviceObserverMojo* observer) {
+  DCHECK(manager_->AreDeviceListsComplete());
+
+  auto& keyboard_devices = manager_->GetKeyboardDevices();
+  auto& touchscreen_devices = manager_->GetTouchscreenDevices();
+  auto& mouse_devices = manager_->GetMouseDevices();
+  auto& touchpad_devices = manager_->GetTouchpadDevices();
+  observer->OnDeviceListsComplete(
+      mojo::Array<ui::InputDevice>::From(keyboard_devices),

[sadrul, 2016/06/10 18:01:49]

Do you need to explicitly do this? i.e. are struct-traits not smart enough to
take care of this?

[kylechar, 2016/06/10 19:29:31]

Ah they are smart enough. Fixed here and above.

+      mojo::Array<ui::TouchscreenDevice>::From(touchscreen_devices),
+      mojo::Array<ui::InputDevice>::From(mouse_devices),
+      mojo::Array<ui::InputDevice>::From(touchpad_devices));
+}
+
+}  // namespace input_device