Adjust focus when it is set to entire List in ARC

Sometimes Android sets the focus (via a11y event of VIEW_FOCUSED) to
the collection (list/grid). This invokes ChromeVox to read entire
content of the collection.

This CL adds following logic to handle the situation:
1. If a role of a node is kList or kGrid, CanBeAccessibilityFocused returns
   false.
2. When a11y event of VIEW_FOCUSED is dispatched, instead of directly
   assigning event source as a focus, try to find the first focusable
   node under the event source.

element of the node gets ChromeVox focus.

Bug: b:130185621
Test: unit_tests --gtest_filter="AXTreeSourceArcTest.*"
Test: manual. Open PlayStore/Hangouts and open drawer menu. The fist
Change-Id: Ic85f05711fbd9cff2e2e074a01daa37c09d71bff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1942902
Commit-Queue: Hiroki Sato <hirokisato@chromium.org>
Reviewed-by: Sara Kato <sarakato@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#721876}

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

@@ -71,7 +71,9 @@ bool AccessibilityNodeInfoDataWrapper::CanBeAccessibilityFocused() const {
   bool important = GetProperty(AXBooleanProperty::IMPORTANCE) ||
                    IsFocusableNativeWeb(data.role);
   bool non_generic_role = data.role != ax::mojom::Role::kGenericContainer &&
-                          data.role != ax::mojom::Role::kGroup;
+                          data.role != ax::mojom::Role::kGroup &&
+                          data.role != ax::mojom::Role::kList &&
+                          data.role != ax::mojom::Role::kGrid;
   bool actionable = is_clickable_leaf_ ||
                     GetProperty(AXBooleanProperty::FOCUSABLE) ||
                     GetProperty(AXBooleanProperty::CHECKABLE);

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

@@ -117,8 +117,13 @@ void AXTreeSourceArc::NotifyAccessibilityEvent(AXEventData* event_data) {
   if (event_data->event_type == AXEventType::VIEW_FOCUSED) {
     AccessibilityInfoDataWrapper* focused_node =
         GetFromId(event_data->source_id);
-    if (focused_node)
-      focused_id_ = event_data->source_id;
+    if (focused_node) {
+      // Sometimes Android sets focus on unfocusable node, e.g. ListView.
+      AccessibilityInfoDataWrapper* adjusted_node =
+          FindFirstFocusableNode(focused_node);
+      focused_id_ = IsValid(adjusted_node) ? adjusted_node->GetId()
+                                           : event_data->source_id;
+    }
   } else if (event_data->event_type == AXEventType::WINDOW_STATE_CHANGED) {
     // When accessibility window changed, a11y event of WINDOW_CONTENT_CHANGED
     // is fired from Android multiple times.

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

@@ -919,7 +919,6 @@ TEST_F(AXTreeSourceArcTest, OnWindowStateChangedEvent) {
 
 TEST_F(AXTreeSourceArcTest, OnFocusEvent) {
   auto event = AXEventData::New();
-  event->source_id = 2;  // node2.
   event->task_id = 1;
   event->event_type = AXEventType::VIEW_FOCUSED;
 
@@ -936,28 +935,41 @@ TEST_F(AXTreeSourceArcTest, OnFocusEvent) {
   SetProperty(root, AXIntListProperty::CHILD_NODE_IDS,
               std::vector<int>({1, 2}));
   SetProperty(root, AXBooleanProperty::IMPORTANCE, true);
+  root->collection_info = AXCollectionInfoData::New();
+  root->collection_info->row_count = 2;
+  root->collection_info->column_count = 1;
 
   event->node_data.emplace_back(AXNodeInfoData::New());
   AXNodeInfoData* node1 = event->node_data.back().get();
   node1->id = 1;
   SetProperty(node1, AXBooleanProperty::IMPORTANCE, true);
   SetProperty(node1, AXBooleanProperty::ACCESSIBILITY_FOCUSED, true);
+  SetProperty(node1, AXBooleanProperty::VISIBLE_TO_USER, true);
   SetProperty(node1, AXStringProperty::TEXT, "sample string1.");
 
   event->node_data.emplace_back(AXNodeInfoData::New());
   AXNodeInfoData* node2 = event->node_data.back().get();
   node2->id = 2;
   SetProperty(node2, AXBooleanProperty::IMPORTANCE, true);
+  SetProperty(node1, AXBooleanProperty::VISIBLE_TO_USER, true);
   SetProperty(node2, AXStringProperty::TEXT, "sample string2.");
 
+  // Chrome should focus to node2, even if node1 has 'focus' in Android.
+  event->source_id = node2->id;
   CallNotifyAccessibilityEvent(event.get());
-  ui::AXTreeData data;
 
-  // Chrome should focus to node2, even if node1 has 'focus' in Android.
+  ui::AXTreeData data;
   EXPECT_TRUE(CallGetTreeData(&data));
   EXPECT_EQ(node2->id, data.focus_id);
 
-  EXPECT_EQ(1, GetDispatchedEventCount(ax::mojom::Event::kFocus));
+  // Chrome should focus to node2, even if Android sends focus on List.
+  event->source_id = root->id;
+  CallNotifyAccessibilityEvent(event.get());
+
+  EXPECT_TRUE(CallGetTreeData(&data));
+  EXPECT_EQ(node1->id, data.focus_id);
+
+  EXPECT_EQ(2, GetDispatchedEventCount(ax::mojom::Event::kFocus));
 }
 
 TEST_F(AXTreeSourceArcTest, SerializeAndUnserialize) {