Move child tree id logic from AutomationManagerAura to WebView

Bug: 888152
Change-Id: I5584ab2c808b26f7363d214bedae38d080ba9735
Reviewed-on: https://chromium-review.googlesource.com/1246168
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#595649}

chrome/browser/ui/aura/accessibility/automation_manager_aura.cc

@@ -10,7 +10,6 @@
 #include "build/build_config.h"
 #include "chrome/browser/extensions/api/automation_internal/automation_event_router.h"
 #include "chrome/common/extensions/chrome_extension_messages.h"
-#include "content/public/browser/ax_event_notification_details.h"
 #include "content/public/browser/render_frame_host.h"
 #include "ui/accessibility/ax_action_data.h"
 #include "ui/accessibility/ax_enum_util.h"

chrome/browser/ui/aura/accessibility/ax_tree_source_aura.cc

@@ -5,8 +5,6 @@
 #include "chrome/browser/ui/aura/accessibility/ax_tree_source_aura.h"
 
 #include "chrome/browser/ui/aura/accessibility/automation_manager_aura.h"
-#include "content/public/browser/render_frame_host.h"
-#include "content/public/browser/web_contents.h"
 #include "ui/accessibility/ax_tree_id.h"
 #include "ui/views/accessibility/ax_aura_obj_wrapper.h"
 #include "ui/views/accessibility/ax_view_obj_wrapper.h"
@@ -30,19 +28,8 @@ views::AXAuraObjWrapper* AXTreeSourceAura::GetRoot() const {
 void AXTreeSourceAura::SerializeNode(views::AXAuraObjWrapper* node,
                                      ui::AXNodeData* out_data) const {
   AXTreeSourceViews::SerializeNode(node, out_data);
-
-  if (out_data->role == ax::mojom::Role::kWebView) {
-    views::View* view = static_cast<views::AXViewObjWrapper*>(node)->view();
-    content::WebContents* contents =
-        static_cast<views::WebView*>(view)->GetWebContents();
-    content::RenderFrameHost* rfh = contents->GetMainFrame();
-    if (rfh) {
-      ui::AXTreeID ax_tree_id = rfh->GetAXTreeID();
-      out_data->AddStringAttribute(ax::mojom::StringAttribute::kChildTreeId,
-                                   ax_tree_id);
-    }
-  } else if (out_data->role == ax::mojom::Role::kWindow ||
-             out_data->role == ax::mojom::Role::kDialog) {
+  if (out_data->role == ax::mojom::Role::kWindow ||
+      out_data->role == ax::mojom::Role::kDialog) {
     // Add clips children flag by default to these roles.
     out_data->AddBoolAttribute(ax::mojom::BoolAttribute::kClipsChildren, true);
   }

ui/views/controls/webview/webview.cc

@@ -258,6 +258,10 @@ void WebView::GetAccessibleNodeData(ui::AXNodeData* node_data) {
   // provided via other means. Providing it here would be redundant.
   // Mark the name as explicitly empty so that accessibility_checks pass.
   node_data->SetNameExplicitlyEmpty();
+  if (child_ax_tree_id_ != ui::AXTreeIDUnknown()) {
+    node_data->AddStringAttribute(ax::mojom::StringAttribute::kChildTreeId,
+                                  child_ax_tree_id_);
+  }
 }
 
 gfx::NativeViewAccessible WebView::GetNativeViewAccessible() {
@@ -415,8 +419,13 @@ void WebView::UpdateCrashedOverlayView() {
 }
 
 void WebView::NotifyAccessibilityWebContentsChanged() {
-  if (web_contents())
-    NotifyAccessibilityEvent(ax::mojom::Event::kChildrenChanged, false);
+  content::RenderFrameHost* rfh =
+      web_contents() ? web_contents()->GetMainFrame() : nullptr;
+  if (rfh)
+    child_ax_tree_id_ = rfh->GetAXTreeID();
+  else
+    child_ax_tree_id_ = ui::AXTreeIDUnknown();
+  NotifyAccessibilityEvent(ax::mojom::Event::kChildrenChanged, false);
 }
 
 std::unique_ptr<content::WebContents> WebView::CreateWebContents(

ui/views/controls/webview/webview.h

@@ -211,6 +211,10 @@ class WEBVIEW_EXPORT WebView : public View,
   gfx::Size min_size_;
   gfx::Size max_size_;
 
+  // Tracks the child accessibility tree id which is associated with the
+  // WebContents's main RenderFrameHost.
+  ui::AXTreeID child_ax_tree_id_;
+
   DISALLOW_COPY_AND_ASSIGN(WebView);
 };