Add Mojo IPC based input-device service.

components/mus/public/cpp/input_devices/lib/input_device_client.cc

Index: components/mus/public/cpp/input_devices/lib/input_device_client.cc
diff --git a/components/mus/public/cpp/input_devices/lib/input_device_client.cc b/components/mus/public/cpp/input_devices/lib/input_device_client.cc
new file mode 100644
index 0000000000000000000000000000000000000000..48a1f52cf97709b901c4f206ec3aacc7cff8ccd9
--- /dev/null
+++ b/components/mus/public/cpp/input_devices/lib/input_device_client.cc
@@ -0,0 +1,128 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.

[Ben Goodger (Google), 2016/06/02 19:35:18]

we're going to get rid of lib subdirs... so just put the .cc alongside the .h

[kylechar, 2016/06/03 14:35:57]

Done. Will upload a new patch after rebasing later today.

+// 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/input_devices/input_device_client.h"
+
+#include "base/bind.h"
+#include "base/files/file_path.h"
+#include "base/logging.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+
+namespace input_device {
+
+namespace {
+
+// TODO(kylechar): Debug, remove eventually.
+template <class DeviceType>
+void PrintDevices(std::string title, const DeviceType& devices) {
+  std::vector<std::string> device_strings;
+  device_strings.push_back(base::StringPrintf("%s devices.size()=%zu",
+                                              title.c_str(), devices.size()));
+  for (const auto& device : devices) {
+    device_strings.push_back(device.ToString());
+  }
+  LOG(ERROR) << base::JoinString(device_strings, ", ");
+}
+
+}  // namespace
+
+InputDeviceClient::InputDeviceClient() : binding_(this) {
+  InputDeviceManager::SetInstance(this);
+}
+
+InputDeviceClient::~InputDeviceClient() {
+  InputDeviceManager::ClearInstance();
+}
+
+void InputDeviceClient::Connect(shell::Connector* connector) {

[Ben Goodger (Google), 2016/06/02 19:35:18]

rather than passing in a connector, can you require the client of this lib
perform this connection & just pass in the InputDeviceServicePtr?

[kylechar, 2016/06/03 14:35:57]

Yeah, that's absolutely possible. I'm just getting familiar with Mojo in
general, is there an advantage to that way? I can see a small disadvantage, as
clients of this lib needs to include the InputDeviceServer mojom and connect to
mus. Is the advantage that we can connect via other means, not just the
shell:Connector?

+  mojom::InputDeviceServerPtr service;
+  connector->ConnectToInterface("mojo:mus", &service);
+
+  // Add this class as an observer via Mojo IPC.
+  service->AddObserver(binding_.CreateInterfacePtrAndBind());
+  binding_.set_connection_error_handler([]() {
+    LOG(ERROR) << "InputDeviceClient failed to bind observer pipe.";
+  });
+}
+
+void InputDeviceClient::OnKeyboardDeviceConfigurationChanged(
+    mojo::Array<ui::InputDevice> devices) {
+  keyboard_devices_ = devices.To<std::vector<ui::InputDevice>>();
+  PrintDevices("UpdateKeyboardDevices", keyboard_devices_);
+  FOR_EACH_OBSERVER(ui::InputDeviceEventObserver, observers_,
+                    OnKeyboardDeviceConfigurationChanged());
+}
+
+void InputDeviceClient::OnTouchscreenDeviceConfigurationChanged(
+    mojo::Array<ui::TouchscreenDevice> devices) {
+  touchscreen_devices_ = devices.To<std::vector<ui::TouchscreenDevice>>();
+  PrintDevices("UpdateTouchscreenDevices", touchscreen_devices_);
+  FOR_EACH_OBSERVER(ui::InputDeviceEventObserver, observers_,
+                    OnTouchscreenDeviceConfigurationChanged());
+}
+
+void InputDeviceClient::OnMouseDeviceConfigurationChanged(
+    mojo::Array<ui::InputDevice> devices) {
+  mouse_devices_ = devices.To<std::vector<ui::InputDevice>>();
+  PrintDevices("UpdateMouseDevices", mouse_devices_);
+  FOR_EACH_OBSERVER(ui::InputDeviceEventObserver, observers_,
+                    OnMouseDeviceConfigurationChanged());
+}
+
+void InputDeviceClient::OnTouchpadDeviceConfigurationChanged(
+    mojo::Array<ui::InputDevice> devices) {
+  touchpad_devices_ = devices.To<std::vector<ui::InputDevice>>();
+  PrintDevices("UpdateTouchpadDevices", touchpad_devices_);
+  FOR_EACH_OBSERVER(ui::InputDeviceEventObserver, observers_,
+                    OnTouchpadDeviceConfigurationChanged());
+}
+
+void InputDeviceClient::OnDeviceListsComplete() {
+  if (!device_lists_complete_) {
+    LOG(ERROR) << "InputDeviceClient::OnDeviceListsComplete";
+    device_lists_complete_ = true;
+    FOR_EACH_OBSERVER(ui::InputDeviceEventObserver, observers_,
+                      OnDeviceListsComplete());
+  }
+}
+
+void InputDeviceClient::AddObserver(ui::InputDeviceEventObserver* observer) {
+  observers_.AddObserver(observer);
+}
+
+void InputDeviceClient::RemoveObserver(ui::InputDeviceEventObserver* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+const std::vector<ui::InputDevice>& InputDeviceClient::GetKeyboardDevices()
+    const {
+  return keyboard_devices_;
+}
+
+const std::vector<ui::TouchscreenDevice>&
+InputDeviceClient::GetTouchscreenDevices() const {
+  return touchscreen_devices_;
+}
+
+const std::vector<ui::InputDevice>& InputDeviceClient::GetMouseDevices() const {
+  return mouse_devices_;
+}
+
+const std::vector<ui::InputDevice>& InputDeviceClient::GetTouchpadDevices()
+    const {
+  return touchpad_devices_;
+}
+
+bool InputDeviceClient::AreDeviceListsComplete() const {
+  return device_lists_complete_;
+}
+
+bool InputDeviceClient::AreTouchscreensEnabled() const {
+  // TODO(kylechar): This obviously isn't right. We either need to pass this
+  // state around or modify the interface.
+  return true;
+}
+
+}  // namespace input_device