Initial support for accessibility actions on ARC.

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.h

 // 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_ACCESSIBILITY_AX_TREE_SOURCE_ARC_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ACCESSIBILITY_AX_TREE_SOURCE_ARC_H_
 
 #include <map>
 #include <memory>
 #include <vector>
@@ skipping 12 matching lines @@
     ui::AXTreeSerializer<mojom::AccessibilityNodeInfoData*,
                          ui::AXNodeData,
                          ui::AXTreeData>;
 
 // This class represents the accessibility tree from the focused ARC window.
 class AXTreeSourceArc
     : public ui::AXTreeSource<mojom::AccessibilityNodeInfoData*,
                               ui::AXNodeData,
                               ui::AXTreeData> {
  public:
-  AXTreeSourceArc();
+  explicit AXTreeSourceArc(int32_t tree_id);
   ~AXTreeSourceArc() override;
 
   // Notify automation of an accessibility event.
   void NotifyAccessibilityEvent(mojom::AccessibilityEventData* event_data);
 
   int32_t tree_id() const { return tree_id_; }
 
  private:
   // AXTreeSource overrides.
   bool GetTreeData(ui::AXTreeData* data) const override;
@@ skipping 24 matching lines @@
   std::unique_ptr<AXTreeArcSerializer> current_tree_serializer_;
   int32_t root_id_;
   int32_t focused_node_id_;
 
   DISALLOW_COPY_AND_ASSIGN(AXTreeSourceArc);
 };
 
 }  // namespace arc
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ACCESSIBILITY_AX_TREE_SOURCE_ARC_H_