Refactor and send voice interaction structure

chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_arc_home_service.h

Index: chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_arc_home_service.h
diff --git a/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_arc_home_service.h b/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_arc_home_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..1be5837c49d24e619caba34e4105a3ae20462fe9
--- /dev/null
+++ b/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_arc_home_service.h
@@ -0,0 +1,55 @@
+// Copyright 2017 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_ARC_VOICE_INTERACTION_ARC_VOICE_INTERACTION_ARC_HOME_SERVICE_H_
+#define CHROME_BROWSER_CHROMEOS_ARC_VOICE_INTERACTION_ARC_VOICE_INTERACTION_ARC_HOME_SERVICE_H_
+
+#include "base/macros.h"
+#include "components/arc/arc_service.h"
+#include "components/arc/common/voice_interaction_arc_home.mojom.h"
+#include "components/arc/instance_holder.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "ui/accessibility/ax_tree_update.h"
+
+namespace ui {
+

[Luis Héctor Chávez, 2017/04/25 18:22:36]

nit: typically fwd-declarations of this style don't have empty lines around the
namespace:

namespace ui {
struct AXSnapshotNodeAndroid;
}  // namespace ui

example:
https://cs.chromium.org/chromium/src/chrome/browser/chromeos/arc/policy/arc_p...

[Muyuan, 2017/04/25 19:38:13]

Done.

+struct AXSnapshotNodeAndroid;
+
+}  // ui
+
+namespace arc {
+
+// ArcVoiceInteractionArcHomeService provides view hierarchy to to ARC to be
+// used by VoiceInteractionSession. This class lives on the UI thread.
+class ArcVoiceInteractionArcHomeService
+    : public ArcService,
+      public mojom::VoiceInteractionArcHomeHost,
+      public InstanceHolder<mojom::VoiceInteractionArcHomeInstance>::Observer {
+ public:
+  explicit ArcVoiceInteractionArcHomeService(ArcBridgeService* bridge_service);
+  ~ArcVoiceInteractionArcHomeService() override;
+
+  // InstanceHolder<mojom::VoiceInteractionArcHomeInstance> overrides;
+  void OnInstanceReady() override;
+
+  // Gets view hierarchy from current focused app and send it to ARC.
+  void GetVoiceInteractionStructure(
+      const GetVoiceInteractionStructureCallback& callback) override;
+
+ private:
+  mojo::Binding<mojom::VoiceInteractionArcHomeHost> binding_;
+
+  static mojom::VoiceInteractionStructurePtr CreateVoiceInteractionStructure(

[Luis Héctor Chávez, 2017/04/25 18:22:36]

it's better to move these private static methods to the anonymous namespace.

If you need to expose one in tests, instead of friending the test you can create
a thin wrapper:

public:
 static mojom::VoiceInteractionStructurePtr
CreateVoiceInteractionStructureForTesting(...);

this one can just call the anonymous namespaced
CreateVoiceInteractionStructure(). See
arc::GetUrlToNavigateOnDeactivateForTesting() for an example.

[Muyuan, 2017/04/25 19:38:13]

Done.

+      const ui::AXSnapshotNodeAndroid& view_structure);
+  static void RequestVoiceInteractionStructureCallback(
+      const base::Callback<void(mojom::VoiceInteractionStructurePtr)>& callback,

[Luis Héctor Chávez, 2017/04/25 18:22:36]

iwyu: #include "base/callback_forward.h"

[Muyuan, 2017/04/25 19:38:13]

Done. Moved to anonymous namespace.

+      const ui::AXTreeUpdate& update);
+
+  friend class ArcVoiceInteractionArcHomeServiceTest;
+
+  DISALLOW_COPY_AND_ASSIGN(ArcVoiceInteractionArcHomeService);
+};
+
+}  // namespace arc
+#endif  // CHROME_BROWSER_CHROMEOS_ARC_VOICE_INTERACTION_ARC_VOICE_INTERACTION_ARC_HOME_SERVICE_H_