Show corresponding window/widget/view in UIElement tree when clicking on a UI element.

components/ui_devtools/views/ui_devtools_dom_agent.h

 // 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.
 
 #ifndef COMPONENTS_UI_DEVTOOLS_VIEWS_UI_DEVTOOLS_DOM_AGENT_H_
 #define COMPONENTS_UI_DEVTOOLS_VIEWS_UI_DEVTOOLS_DOM_AGENT_H_
 
 #include "components/ui_devtools/DOM.h"
 #include "components/ui_devtools/devtools_base_agent.h"
 #include "components/ui_devtools/views/ui_element_delegate.h"
 #include "ui/aura/env_observer.h"
+#include "ui/events/event_handler.h"
 #include "ui/views/view.h"
 #include "ui/views/widget/widget.h"
 
 namespace aura {
 class Window;
 }
 
+namespace ui {
+class MouseEvent;
+}
+
 namespace ui_devtools {
 
+class UIDevToolsOverlayAgent;
 class UIElement;
 
 class UIDevToolsDOMAgentObserver {
  public:
   // TODO(thanhph): Use UIElement* as input argument instead.
   virtual void OnNodeBoundsChanged(int node_id) = 0;
 };
 
 class UIDevToolsDOMAgent : public ui_devtools::UiDevToolsBaseAgent<
                                ui_devtools::protocol::DOM::Metainfo>,
                            public UIElementDelegate,
-                           public aura::EnvObserver {
+                           public aura::EnvObserver,
+                           public ui::EventHandler {
  public:
-  UIDevToolsDOMAgent();
+  UIDevToolsDOMAgent(UIDevToolsOverlayAgent* overlay_agent);
   ~UIDevToolsDOMAgent() override;
 
   // DOM::Backend:
   ui_devtools::protocol::Response disable() override;
   ui_devtools::protocol::Response getDocument(
       std::unique_ptr<ui_devtools::protocol::DOM::Node>* out_root) override;
   ui_devtools::protocol::Response highlightNode(
       std::unique_ptr<ui_devtools::protocol::DOM::HighlightConfig>
           highlight_config,
       ui_devtools::protocol::Maybe<int> node_id) override;
+  ui_devtools::protocol::Response setInspectMode(
+      ui_devtools::protocol::Maybe<String> mode,
+      std::unique_ptr<ui_devtools::protocol::DOM::HighlightConfig>
+          highlight_config,
+      ui_devtools::protocol::Maybe<int> node_id) override;
   ui_devtools::protocol::Response hideHighlight() override;
 
   // UIElementDelegate:
   void OnUIElementAdded(UIElement* parent, UIElement* child) override;
   void OnUIElementReordered(UIElement* parent, UIElement* child) override;
   void OnUIElementRemoved(UIElement* ui_element) override;
   void OnUIElementBoundsChanged(UIElement* ui_element) override;
   bool IsHighlightingWindow(aura::Window* window) override;
 
+  // ui:EventHandler:
+  void OnMouseEvent(ui::MouseEvent* event) override;
+
   void AddObserver(UIDevToolsDOMAgentObserver* observer);
   void RemoveObserver(UIDevToolsDOMAgentObserver* observer);
   UIElement* GetElementFromNodeId(int node_id);
   UIElement* window_element_root() const { return window_element_root_.get(); };
   const std::vector<aura::Window*>& root_windows() const {
     return root_windows_;
   };
 
  private:
   // aura::EnvObserver:
@@ skipping 18 matching lines @@
   void InitializeHighlightingWidget();
   void UpdateHighlight(
       const std::pair<aura::Window*, gfx::Rect>& window_and_bounds,
       SkColor background,
       SkColor border);
   ui_devtools::protocol::Response HighlightNode(
       std::unique_ptr<ui_devtools::protocol::DOM::HighlightConfig>
           highlight_config,
       int node_id);
 
+  UIDevToolsOverlayAgent* overlay_agent_;
   bool is_building_tree_;
   std::unique_ptr<UIElement> window_element_root_;
   std::unordered_map<int, UIElement*> node_id_to_ui_element_;
   std::unique_ptr<views::Widget> widget_for_highlighting_;
   std::vector<aura::Window*> root_windows_;
   base::ObserverList<UIDevToolsDOMAgentObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(UIDevToolsDOMAgent);
 };
 
 }  // namespace ui_devtools
 
 #endif  // COMPONENTS_UI_DEVTOOLS_VIEWS_UI_DEVTOOLS_DOM_AGENT_H_