Too many accessible nodes were marked as clickable on Android

content/browser/accessibility/browser_accessibility_manager_android.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/accessibility/browser_accessibility_manager_android.h"
 
 #include <stddef.h>
 
 #include <cmath>
 
@@ skipping 36 matching lines @@
     case ui::AX_ROLE_MAIN:
     case ui::AX_ROLE_NAVIGATION:
     case ui::AX_ROLE_SEARCH:
     case ui::AX_ROLE_REGION:
       return true;
     default:
       return false;
   }
 }
 
+bool AllInterestingNodesPredicate(
+    BrowserAccessibility* start, BrowserAccessibility* node) {
+  // Focusable nodes should never be skipped. Note that IsFocusable()
+  // already skips over things like iframes and child frames that are
+  // technically focusable but shouldn't be exposed as focusable on Android.
+  BrowserAccessibilityAndroid* android_node =
+      static_cast<BrowserAccessibilityAndroid*>(node);
+  if (android_node->IsFocusable())
+    return true;
+
+  // Otherwise, the interesting nodes are leaf nodes with text.

[David Tseng, 2016/10/12 20:28:35]

If I have a <div role="button"> (no text content, not focusable), it's not
interesting?

[dmazzoni, 2016/10/12 22:41:58]

Good idea, I can have it return true if it's a control role.

+  return node->PlatformIsLeaf() && !node->GetText().empty();
+}
+
 void AddToPredicateMap(const char* search_key_ascii,
                        AccessibilityMatchPredicate predicate) {
   base::string16 search_key_utf16 = base::ASCIIToUTF16(search_key_ascii);
   g_search_key_to_predicate_map.Get()[search_key_utf16] = predicate;
   if (!g_all_search_keys.Get().empty())
     g_all_search_keys.Get() += base::ASCIIToUTF16(",");
   g_all_search_keys.Get() += search_key_utf16;
 }
 
 // These are special unofficial strings sent from TalkBack/BrailleBack
@@ skipping 31 matching lines @@
   AddToPredicateMap("VISITED_LINK", AccessibilityVisitedLinkPredicate);
 }
 
 AccessibilityMatchPredicate PredicateForSearchKey(
     const base::string16& element_type) {
   InitSearchKeyToPredicateMapIfNeeded();
   const auto& iter = g_search_key_to_predicate_map.Get().find(element_type);
   if (iter != g_search_key_to_predicate_map.Get().end())
     return iter->second;
 
-  // If we don't recognize the selector, return any element that's clickable.
-  // We mark all focusable nodes and leaf nodes as clickable because it's
-  // impossible to know whether a web node has a click handler or not, so
-  // to be safe we have to allow accessibility services to click on nearly
-  // anything that could possibly respond to a click.
-  return [](BrowserAccessibility* start, BrowserAccessibility* node) {
-    return static_cast<BrowserAccessibilityAndroid*>(node)->IsClickable();
-  };
+  // If we don't recognize the selector, return any element that a
+  // screen reader should navigate to.
+  return AllInterestingNodesPredicate;
 }
 
 }  // anonymous namespace
 
 namespace aria_strings {
   const char kAriaLivePolite[] = "polite";
   const char kAriaLiveAssertive[] = "assertive";
 }
 
 // static
@@ skipping 818 matching lines @@
 
   JNIEnv* env = AttachCurrentThread();
   return root_manager->java_ref().get(env);
 }
 
 bool RegisterBrowserAccessibilityManager(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace content