kMenuItem valid child of kMenuListOption for PosInSet/SetSize.

This change allows kMenuItems to be valid children of kMenuListOption
elements for PosInSet and SetSize calculations. The motivating example
for this change was navigating through the app menu in the Chrome
toolbar using ChromeVox(the menu that contains buttons for new tab,
history, downloads, bookmarks, dev tools, etc.). ChromeVox would report
PosInSet and SetSize of 0 for many elements, due to the fact that
the elements are held within a kMenuListOption, not a kMenu. In the
PosInSet and SetSize code, we have checks to ensure valid parent-child
relationships. This is a case that must have been missed in the
initial implementation.

Change-Id: I8ab6182862cb9a4112d525044046a1e15048fc5e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1757467
Commit-Queue: Akihiro Ota <akihiroota@chromium.org>
Reviewed-by: Aaron Leventhal <aleventhal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#688669}

ui/accessibility/ax_node.cc

@@ -785,7 +785,8 @@ bool AXNode::SetRoleMatchesItemRole(const AXNode* ordered_set) const {
     case ax::mojom::Role::kListBox:
       return item_role == ax::mojom::Role::kListBoxOption;
     case ax::mojom::Role::kMenuListPopup:
-      return item_role == ax::mojom::Role::kMenuListOption;
+      return item_role == ax::mojom::Role::kMenuListOption ||
+             item_role == ax::mojom::Role::kMenuItem;
     case ax::mojom::Role::kRadioGroup:
       return item_role == ax::mojom::Role::kRadioButton;
     case ax::mojom::Role::kDescriptionList:

ui/accessibility/ax_tree_unittest.cc

@@ -3337,6 +3337,29 @@ TEST(AXTreeTest, TestSetSizePosInSetUnkown) {
   EXPECT_OPTIONAL_EQ(2, item2->GetSetSize());
 }
 
+TEST(AXTreeTest, TestSetSizePosInSetMenuItemValidChildOfMenuListPopup) {
+  AXTreeUpdate initial_state;
+  initial_state.root_id = 1;
+  initial_state.nodes.resize(3);
+  initial_state.nodes[0].id = 1;
+  initial_state.nodes[0].child_ids = {2, 3};
+  initial_state.nodes[0].role = ax::mojom::Role::kMenuListPopup;
+  initial_state.nodes[1].id = 2;
+  initial_state.nodes[1].role = ax::mojom::Role::kMenuItem;
+  initial_state.nodes[2].id = 3;
+  initial_state.nodes[2].role = ax::mojom::Role::kMenuListOption;
+  AXTree tree(initial_state);
+
+  AXNode* menu = tree.GetFromId(1);
+  EXPECT_OPTIONAL_EQ(2, menu->GetSetSize());
+  AXNode* item1 = tree.GetFromId(2);
+  EXPECT_OPTIONAL_EQ(1, item1->GetPosInSet());
+  EXPECT_OPTIONAL_EQ(2, item1->GetSetSize());
+  AXNode* item2 = tree.GetFromId(3);
+  EXPECT_OPTIONAL_EQ(2, item2->GetPosInSet());
+  EXPECT_OPTIONAL_EQ(2, item2->GetSetSize());
+}
+
 TEST(AXTreeTest, OnNodeWillBeDeletedHasValidUnignoredParent) {
   AXTreeUpdate initial_state;
   initial_state.root_id = 1;