Ensure ChromeVox descends into buttons to click on YouTube videos in ARC

R=hirokisato@chromium.org

clickable text to play each video

Bug: none
Change-Id: I9f01f111fdcce6665a4eabd872ad9778d64ed6f2
AX-Relnotes: Within the YouTube Android app, ChromeVox can navigate to the
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2450890
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Hiroki Sato <hirokisato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#814930}

chrome/browser/resources/chromeos/accessibility/chromevox/background/background_test.js

@@ -3133,3 +3133,30 @@ TEST_F('ChromeVoxBackgroundTest', 'ReadFromHereBlankNodes', function() {
         .replay();
   });
 });
+
+TEST_F('ChromeVoxBackgroundTest', 'ContainerButtons', function() {
+  const mockFeedback = this.createMockFeedback();
+
+  // This pattern can be found in ARC++/YouTube.
+  const site = `
+    <p>videos</p>
+    <div aria-label="Cat Video" role="button">
+      <div role="group">4 minutes, Cat Video</div>
+    </div>
+  `;
+  this.runWithLoadedTree(site, function(root) {
+    const group = root.find({role: RoleType.GROUP});
+
+    Object.defineProperty(group, 'clickable', {
+      get() {
+        return true;
+      }
+    });
+
+    mockFeedback.call(doCmd('nextObject'))
+        .expectSpeech('Cat Video', 'Button')
+        .call(doCmd('nextObject'))
+        .expectSpeech('4 minutes, Cat Video')
+        .replay();
+  });
+});

chrome/browser/resources/chromeos/accessibility/common/automation_predicate.js

@@ -20,22 +20,42 @@ const Role = chrome.automation.RoleType;
 const State = chrome.automation.StateType;
 
 /**
- * A helper to find any actionable children.
+ * A helper to check if |node| or any descendant is actionable.
  * @param {!AutomationNode} node
  * @return {boolean}
  */
-const hasActionableDescendant = function(node) {
+const isActionableOrHasActionableDescendant = function(node) {
   // DefaultActionVerb does not have value 'none' even though it gets set.
   if (node.defaultActionVerb != 'none') {
     return true;
   }
 
-  let result = false;
+  if (node.clickable) {
+    return true;
+  }
+
+  for (let i = 0; i < node.children.length; i++) {
+    if (isActionableOrHasActionableDescendant(node.children[i])) {
+      return true;
+    }
+  }
+
+  return false;
+};
+
+/**
+ * A helper to check if any descendants of |node| are actionable.
+ * @param {!AutomationNode} node
+ * @return {boolean}
+ */
+const hasActionableDescendant = function(node) {
   for (let i = 0; i < node.children.length; i++) {
-    result = hasActionableDescendant(node.children[i]);
+    if (isActionableOrHasActionableDescendant(node.children[i])) {
+      return true;
+    }
   }
 
-  return result;
+  return false;
 };
 
 /**
@@ -173,9 +193,9 @@ AutomationPredicate = class {
         // A node acting as a label should be a leaf if it has no actionable
         // controls.
         (!!node.labelFor && node.labelFor.length > 0 &&
-         !hasActionableDescendant(node)) ||
+         !isActionableOrHasActionableDescendant(node)) ||
         (!!node.descriptionFor && node.descriptionFor.length > 0 &&
-         !hasActionableDescendant(node)) ||
+         !isActionableOrHasActionableDescendant(node)) ||
         (node.activeDescendantFor && node.activeDescendantFor.length > 0) ||
         node.state[State.INVISIBLE] || node.children.every(function(n) {
           return n.state[State.INVISIBLE];
@@ -237,6 +257,12 @@ AutomationPredicate = class {
       return false;
     }
 
+    // Things explicitly marked clickable (used only on ARC++) should be
+    // visited.
+    if (node.clickable) {
+      return true;
+    }
+
     // Given no other information, ChromeVox wants to visit focusable
     // (e.g. tabindex=0) nodes only when it has a name or is a control.
     if (node.state[State.FOCUSABLE] &&
@@ -322,6 +348,12 @@ AutomationPredicate = class {
       return false;
     }
 
+    // Always try to dive into subtrees with actionable descendants for some
+    // roles even if these roles are not naturally containers.
+    if (node.role == Role.BUTTON && hasActionableDescendant(node)) {
+      return true;
+    }
+
     return AutomationPredicate.match({
       anyRole: [
         Role.GENERIC_CONTAINER, Role.DOCUMENT, Role.GROUP, Role.LIST,
@@ -418,13 +450,13 @@ AutomationPredicate = class {
     // Ignore nodes acting as labels for another control, that don't
     // have actionable descendants.
     if (node.labelFor && node.labelFor.length > 0 &&
-        !hasActionableDescendant(node)) {
+        !isActionableOrHasActionableDescendant(node)) {
       return true;
     }
 
     // Similarly, ignore nodes acting as descriptions.
     if (node.descriptionFor && node.descriptionFor.length > 0 &&
-        !hasActionableDescendant(node)) {
+        !isActionableOrHasActionableDescendant(node)) {
       return true;
     }
 

chrome/browser/resources/chromeos/accessibility/common/automation_util_test.js

@@ -228,7 +228,7 @@ TEST_F(
       this.runWithLoadedTree(
           `
     <div role="button" aria-label="outer">
-      <div role="button" aria-label="inner">
+      <div role="heading" aria-label="inner">
       </div>
     </div>
     `,