Properly prioritize the sources of an accessible name on Android.

content/browser/accessibility/browser_accessibility_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_android.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "content/browser/accessibility/browser_accessibility_manager_android.h"
 #include "content/common/accessibility_messages.h"
 
@@ skipping 250 matching lines @@
 
   return class_name;
 }
 
 base::string16 BrowserAccessibilityAndroid::GetText() const {
   if (IsIframe() ||
       GetRole() == ui::AX_ROLE_WEB_AREA) {
     return base::string16();
   }
 
+  // See comment in browser_accessibility_win.cc for details.
+  // The difference here is that we can only expose one accessible
+  // name on Android, not 2 or 3 like on Windows or Mac.
+  //
+  // The basic rule is: prefer description (aria-labelledby or aria-label),
+  // then help (title), then name (inner text), then value (control value).
+  // However, if title_elem_id is set, that means there's a label element
+  // supplying the name and then name takes precedence over help.
+  // TODO(dmazzoni): clean this up by providing more granular labels in
+  // Blink, making the platform-specific mapping to accessible text simpler.
   base::string16 description = GetString16Attribute(ui::AX_ATTR_DESCRIPTION);
+  base::string16 help = GetString16Attribute(ui::AX_ATTR_HELP);
+  int title_elem_id = GetIntAttribute(
+      ui::AX_ATTR_TITLE_UI_ELEMENT);
   base::string16 text;
-  if (!name().empty())
+  if (!description.empty())
+    text = description;
+  else if (title_elem_id && !name().empty())
     text = base::UTF8ToUTF16(name());
-  else if (!description.empty())
-    text = description;
+  else if (!help.empty())
+    text = help;
+  else if (!name().empty())
+    text = base::UTF8ToUTF16(name());
   else if (!value().empty())
     text = base::UTF8ToUTF16(value());
 
   // This is called from PlatformIsLeaf, so don't call PlatformChildCount
   // from within this!
   if (text.empty() && HasOnlyStaticTextChildren()) {
     for (uint32 i = 0; i < InternalChildCount(); i++) {
       BrowserAccessibility* child = InternalGetChild(i);
       text += static_cast<BrowserAccessibilityAndroid*>(child)->GetText();
     }
@@ skipping 339 matching lines @@
 int BrowserAccessibilityAndroid::CountChildrenWithRole(ui::AXRole role) const {
   int count = 0;
   for (uint32 i = 0; i < PlatformChildCount(); i++) {
     if (PlatformGetChild(i)->GetRole() == role)
       count++;
   }
   return count;
 }
 
 }  // namespace content