Reimplement automation API on top of C++-backed AXTree.

chrome/browser/extensions/api/automation_internal/automation_web_contents_observer.cc

+// Copyright 2014 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 "chrome/browser/extensions/api/automation_internal/automation_web_contents_observer.h"
+
+#include "chrome/browser/accessibility/ax_tree_id_registry.h"
+#include "chrome/browser/extensions/api/automation_internal/automation_event_router.h"
+#include "chrome/common/extensions/chrome_extension_messages.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/render_process_host.h"
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(extensions::AutomationWebContentsObserver);
+
+namespace extensions {
+
+void AutomationWebContentsObserver::AccessibilityEventReceived(
+    const std::vector<content::AXEventNotificationDetails>& details) {
+  std::vector<content::AXEventNotificationDetails>::const_iterator iter =
+      details.begin();
+  for (; iter != details.end(); ++iter) {
+    const content::AXEventNotificationDetails& event = *iter;
+    int tree_id = AXTreeIDRegistry::GetInstance()->GetOrCreateAXTreeID(
+        event.process_id, event.routing_id);
+    ExtensionMsg_AccessibilityEventParams params;
+    params.tree_id = tree_id;
+    params.id = event.id;
+    params.event_type = event.event_type;
+    params.update.node_id_to_clear = event.node_id_to_clear;
+    params.update.nodes = event.nodes;
+    params.location_offset =
+        web_contents()->GetContainerBounds().OffsetFromOrigin();
+
+    AutomationEventRouter* router = AutomationEventRouter::GetInstance();
+    router->DispatchAccessibilityEvent(params);
+  }
+}
+
+void AutomationWebContentsObserver::RenderFrameDeleted(
+    content::RenderFrameHost* render_frame_host) {
+  int tree_id = AXTreeIDRegistry::GetInstance()->GetOrCreateAXTreeID(
+      render_frame_host->GetProcess()->GetID(),
+      render_frame_host->GetRoutingID());
+  AXTreeIDRegistry::GetInstance()->RemoveAXTreeID(tree_id);
+
+  AutomationEventRouter::GetInstance()->DispatchTreeDestroyedEvent(
+      tree_id,
+      browser_context_);
+}
+
+AutomationWebContentsObserver::AutomationWebContentsObserver(
+    content::WebContents* web_contents)
+    : content::WebContentsObserver(web_contents),
+      browser_context_(web_contents->GetBrowserContext()) {}
+
+}  // namespace extensions