Reland: Use AXNode::GetSetSize/AXNode::GetPosInSet unconditionally

Fixed issue by only using the AXTree::GetPosInSet/AXTree::GetSetSize heuristics if they provide a nonzero answer. Otherwise, fall back to raw attributes.
This also exposes pos in set/set size if they are set without doing a role check as some renderers like ARC++ have no such restrictions.

TBR=dmazzoni@chromium.org
Original change description:
This moves ChromeVox to use AXNode::GetSetSize and AXNode::GetPosInSet through their automation bindings.

One issue is fixed:

In AXTree:PopulateOrderedSetItems, an assumption is made that the first child node of the ordered set node, should determine the hierarchical level of the current layer of items.

Unfortunately, for trees like:
tree
  static text
  tree item
  ...

this hueristic fails. See output_test.extjs::NestedLists.

Test: browser_tests --gtest_filter=ChromeVoxOutput*.*
Change-Id: I54911673215e245808a88fab07275a83c2d7109d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1536470Reviewed-by: David Tseng <dtseng@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Akihiro Ota <akihiroota@chromium.org>
Commit-Queue: David Tseng <dtseng@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#645669}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1560015
Cr-Commit-Position: refs/heads/master@{#649245}

chrome/browser/resources/chromeos/chromevox/cvox2/background/output.js

@@ -464,13 +464,12 @@ Output.RULES = {
           $if($inPageLinkTarget, @internal_link, $role) $description`,
     },
     list: {
-      enter: `$role @@list_with_items($countChildren(listItem))`,
+      enter: `$role @@list_with_items($setSize)`,
       speak: `$nameFromNode $descendants $role
-          @@list_with_items($countChildren(listItem)) $description $state`
+          @@list_with_items($setSize) $description $state`
     },
     listBox: {
-      enter: `$nameFromNode
-          $role @@list_with_items($countChildren(listBoxOption))
+      enter: `$nameFromNode $role @@list_with_items($setSize)
           $restriction $description`
     },
     listBoxOption: {
@@ -485,29 +484,23 @@ Output.RULES = {
     menu: {
       enter: `$name $role `,
       speak: `$name $node(activeDescendant)
-          $role @@list_with_items(
-              $countChildren(menuItem, menuItemCheckBox, menuItemRadio))
-          $description $state $restriction`
+          $role @@list_with_items($setSize) $description $state $restriction`
     },
     menuItem: {
       speak: `$name $role $if($hasPopup, @has_submenu)
-          @describe_index($if($posInSet, $posInSet, $indexInParent(menuItem, menuItemCheckBox, menuItemRadio)),
-              $if($setSize, $setSize, $parentChildCount(menuItem, menuItemCheckBox, menuItemRadio)))
-          $description $state $restriction`
+          @describe_index($posInSet, $setSize) $description $state $restriction`
     },
     menuItemCheckBox: {
       speak: `$if($checked, $earcon(CHECK_ON), $earcon(CHECK_OFF))
           $name $role $checked $state $restriction $description
-          @describe_index($if($posInSet, $posInSet, $indexInParent(menuItem, menuItemCheckBox, menuItemRadio)),
-              $if($setSize, $setSize, $parentChildCount(menuItem, menuItemCheckBox, menuItemRadio))) `
+          @describe_index($posInSet, $setSize)`
     },
     menuItemRadio: {
       speak: `$if($checked, $earcon(CHECK_ON), $earcon(CHECK_OFF))
           $if($checked, @describe_radio_selected($name),
           @describe_radio_unselected($name)) $state $roleDescription
           $restriction $description
-          @describe_index($if($posInSet, $posInSet, $indexInParent(menuItem, menuItemCheckBox, menuItemRadio)),
-              $if($setSize, $setSize, $parentChildCount(menuItem, menuItemCheckBox, menuItemRadio))) `
+          @describe_index($posInSet, $setSize)`
     },
     menuListOption: {
       speak: `$name $role @describe_index($posInSet, $setSize) $state
@@ -578,10 +571,7 @@ Output.RULES = {
           $name $role $pressed $description $state $restriction`
     },
     toolbar: {enter: `$name $role $description $restriction`},
-    tree: {
-      enter: `$name $role @@list_with_items($countChildren(treeItem))
-          $restriction`
-    },
+    tree: {enter: `$name $role @@list_with_items($setSize) $restriction`},
     treeItem: {
       enter: `$role $expanded $collapsed $restriction
           @describe_index($posInSet, $setSize)
@@ -1321,25 +1311,6 @@ Output.prototype = {
             this.append_(buff, String(count));
             ruleStr.writeTokenWithValue(token, String(count));
           }
-        } else if (token == 'parentChildCount') {
-          if (node.parent) {
-            options.annotation.push(token);
-            var roles;
-            if (tree.firstChild) {
-              roles = this.createRoles_(tree);
-            } else {
-              roles = new Set();
-              roles.add(node.role);
-            }
-
-            var count = node.parent.children
-                            .filter(function(child) {
-                              return roles.has(child.role);
-                            })
-                            .length;
-            this.append_(buff, String(count));
-            ruleStr.writeTokenWithValue(token, String(count));
-          }
         } else if (token == 'restriction') {
           var msg = Output.RESTRICTION_STATE_MAP[node.restriction];
           if (msg) {
@@ -1590,13 +1561,9 @@ Output.prototype = {
             this.format_(node, '$indexInParent', buff, ruleStr);
           }
         } else if (token == 'setSize') {
-          if (node.setSize !== undefined) {
-            this.append_(buff, String(node.setSize));
+          var size = node.setSize ? node.setSize : 0;
+          this.append_(buff, String(size));
           ruleStr.writeTokenWithValue(token, String(node.setSize));
-          } else {
-            ruleStr.writeToken(token);
-            this.format_(node, '$parentChildCount', buff, ruleStr);
-          }
         } else if (tree.firstChild) {
           // Custom functions.
           if (token == 'if') {
@@ -1630,16 +1597,6 @@ Output.prototype = {
                 tree.firstChild.value, node.location || undefined));
             this.append_(buff, '', options);
             ruleStr.writeTokenWithValue(token, tree.firstChild.value);
-          } else if (token == 'countChildren') {
-            var roles = this.createRoles_(tree);
-
-            var count = node.children
-                            .filter(function(e) {
-                              return roles.has(e.role);
-                            })
-                            .length;
-            this.append_(buff, String(count));
-            ruleStr.writeTokenWithValue(token, String(count));
           }
         }
       } else if (prefix == '@') {

chrome/renderer/extensions/automation_internal_custom_bindings.cc

@@ -818,14 +818,12 @@ void AutomationInternalCustomBindings::AddRoutes() {
             ui::ParseIntAttribute(attribute_name.c_str());
         int attr_value;
 
-        if (attribute == ax::mojom::IntAttribute::kPosInSet) {
+        if (attribute == ax::mojom::IntAttribute::kPosInSet &&
+            node->GetPosInSet()) {
           attr_value = node->GetPosInSet();
-          if (attr_value == 0)
-            return;
-        } else if (attribute == ax::mojom::IntAttribute::kSetSize) {
+        } else if (attribute == ax::mojom::IntAttribute::kSetSize &&
+                   node->GetSetSize()) {
           attr_value = node->GetSetSize();
-          if (attr_value == 0)
-            return;
         } else if (!node->data().GetIntAttribute(attribute, &attr_value)) {
           return;
         }

ui/accessibility/ax_tree.cc

@@ -946,13 +946,16 @@ void AXTree::PopulateOrderedSetItems(const AXNode* ordered_set,
   int original_level = original_node.GetIntAttribute(
       ax::mojom::IntAttribute::kHierarchicalLevel);
   // If original node is ordered set, then set its hierarchical level equal to
-  // its first child to ensure the items vector gets populated.
-  // This is due to ordered sets having a hierarchical level of 0, while their
-  // nodes have non-zero hierarchical values.
-  if ((ordered_set == &original_node) &&
-      ordered_set->GetUnignoredChildAtIndex(0)) {
-    original_level = ordered_set->GetUnignoredChildAtIndex(0)->GetIntAttribute(
+  // its first child that sets a hierarchical level, if any.
+  if (ordered_set == &original_node) {
+    for (int32_t i = 0; i < original_node.GetUnignoredChildCount(); ++i) {
+      int32_t level =
+          original_node.GetUnignoredChildAtIndex(i)->GetIntAttribute(
               ax::mojom::IntAttribute::kHierarchicalLevel);
+      if (level)
+        original_level =
+            original_level ? std::min(level, original_level) : level;
+    }
   }
   int original_node_index = original_node.GetUnignoredIndexInParent();
   bool node_is_radio_button =