Do not ignore WebView and its child nodes for ARC++ a11y

crrev/c/1875853 wired Android's ImportantForAccessibility to chrome's
ignored state. This made all WebView nodes ignored as they don't have
importance.

This CL fixes it by checking whether it's a native web node and it's
focusable.

Bug: b:143435799
Test: unit_tests --gtest_filter="AXTreeSourceArcTest.*"
Change-Id: I01b52b2542d771749c50f44be361572bb30916da
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1890407
Commit-Queue: Hiroki Sato <hirokisato@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Reviewed-by: Sara Kato <sarakato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712414}

chrome/browser/chromeos/arc/accessibility/accessibility_node_info_data_wrapper.cc

@@ -9,6 +9,7 @@
 #include "chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.h"
 #include "ui/accessibility/ax_enums.mojom.h"
 #include "ui/accessibility/ax_node.h"
+#include "ui/accessibility/ax_role_properties.h"
 #include "ui/accessibility/platform/ax_android_constants.h"
 
 namespace arc {
@@ -261,7 +262,11 @@ void AccessibilityNodeInfoDataWrapper::PopulateAXState(
   if (!GetProperty(AXBooleanProperty::VISIBLE_TO_USER))
     out_data->AddState(ax::mojom::State::kInvisible);
 
-  if (!GetProperty(AXBooleanProperty::IMPORTANCE))
+  // WebView and its child nodes do not have accessibility importance set.
+  // IsFocusableNativeWeb can be removed once the change in crrev/c/1890402 is
+  // landed in all ARC containers.
+  if (!GetProperty(AXBooleanProperty::IMPORTANCE) &&
+      !IsFocusableNativeWeb(out_data->role))
     out_data->AddState(ax::mojom::State::kIgnored);
 }
 
@@ -580,4 +585,45 @@ void AccessibilityNodeInfoDataWrapper::ComputeNameFromContents(
   }
 }
 
+// Returns true if the node is (or is inside) WebView and it's accessibility
+// focusable.
+bool AccessibilityNodeInfoDataWrapper::IsFocusableNativeWeb(
+    ax::mojom::Role role) const {
+  std::vector<int32_t> standard_action_ids;
+  if (GetProperty(AXIntListProperty::STANDARD_ACTION_IDS,
+                  &standard_action_ids)) {
+    bool is_native_web = false;
+    bool is_focusable = GetProperty(AXBooleanProperty::FOCUSABLE);
+    for (const int32_t id : standard_action_ids) {
+      switch (static_cast<AXActionType>(id)) {
+        case AXActionType::NEXT_HTML_ELEMENT:
+        case AXActionType::PREVIOUS_HTML_ELEMENT:
+          is_native_web = true;
+          break;
+        case AXActionType::CLICK:
+        case AXActionType::FOCUS:
+        case AXActionType::ACCESSIBILITY_FOCUS:
+          is_focusable = true;
+          break;
+        default:
+          // unused.
+          break;
+      }
+    }
+    return is_native_web &&
+           (is_focusable || ui::IsControl(role) || IsInterestingLeaf());
+  }
+  return false;
+}
+
+bool AccessibilityNodeInfoDataWrapper::IsInterestingLeaf() const {
+  bool has_text = HasProperty(AXStringProperty::CONTENT_DESCRIPTION) ||
+                  HasProperty(AXStringProperty::TEXT);
+  std::vector<AccessibilityInfoDataWrapper*> children;
+  GetChildren(&children);
+  // TODO(hirokisato) Even if the node has children, they might be empty. In
+  // this case we should return true.
+  return has_text && children.empty();
+}
+
 }  // namespace arc

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

@@ -55,6 +55,10 @@ class AccessibilityNodeInfoDataWrapper : public AccessibilityInfoDataWrapper {
   void ComputeNameFromContents(const AccessibilityNodeInfoDataWrapper* data,
                                std::vector<std::string>* names) const;
 
+  bool IsFocusableNativeWeb(ax::mojom::Role role) const;
+
+  bool IsInterestingLeaf() const;
+
   mojom::AccessibilityNodeInfoData* node_ptr_ = nullptr;
 
   bool is_clickable_leaf_;

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc_unittest.cc

@@ -17,6 +17,7 @@
 
 namespace arc {
 
+using AXActionType = mojom::AccessibilityActionType;
 using AXBooleanProperty = mojom::AccessibilityBooleanProperty;
 using AXCollectionInfoData = mojom::AccessibilityCollectionInfoData;
 using AXCollectionItemInfoData = mojom::AccessibilityCollectionItemInfoData;
@@ -940,4 +941,48 @@ TEST_F(AXTreeSourceArcTest, SerializeAndUnserialize) {
   EXPECT_EQ(1U, tree()->GetFromId(10)->GetUnignoredChildCount());
 }
 
+TEST_F(AXTreeSourceArcTest, SerializeWebView) {
+  auto event = AXEventData::New();
+  event->source_id = 10;
+  event->task_id = 1;
+  event->event_type = AXEventType::VIEW_FOCUSED;
+
+  event->window_data = std::vector<mojom::AccessibilityWindowInfoDataPtr>();
+  event->window_data->emplace_back(AXWindowInfoData::New());
+  AXWindowInfoData* root_window = event->window_data->back().get();
+  root_window->window_id = 100;
+  root_window->root_node_id = 10;
+
+  event->node_data.emplace_back(AXNodeInfoData::New());
+  AXNodeInfoData* root = event->node_data.back().get();
+  root->id = 10;
+  SetProperty(root, AXIntListProperty::CHILD_NODE_IDS, std::vector<int>({1}));
+  SetProperty(root, AXBooleanProperty::IMPORTANCE, true);
+
+  // node1 is a webView
+  event->node_data.emplace_back(AXNodeInfoData::New());
+  AXNodeInfoData* node1 = event->node_data.back().get();
+  node1->id = 1;
+  SetProperty(node1, AXIntListProperty::CHILD_NODE_IDS, std::vector<int>({2}));
+  SetProperty(node1, AXStringProperty::CHROME_ROLE, "rootWebArea");
+
+  event->node_data.emplace_back(AXNodeInfoData::New());
+  AXNodeInfoData* node2 = event->node_data.back().get();
+  node2->id = 2;
+  SetProperty(
+      node2, AXIntListProperty::STANDARD_ACTION_IDS,
+      std::vector<int>({static_cast<int>(AXActionType::NEXT_HTML_ELEMENT),
+                        static_cast<int>(AXActionType::FOCUS)}));
+
+  CallNotifyAccessibilityEvent(event.get());
+
+  std::unique_ptr<ui::AXNodeData> data;
+  CallSerializeNode(node1, &data);
+  ASSERT_EQ(ax::mojom::Role::kGenericContainer, data->role);
+
+  // Node inside a WebView is not ignored even if it's not set importance.
+  CallSerializeNode(node2, &data);
+  ASSERT_FALSE(data->HasState(ax::mojom::State::kIgnored));
+}
+
 }  // namespace arc