Expose semantics of landmark and related roles for assitive technologies

content/renderer/accessibility/accessibility_node_serializer.cc

 // Copyright (c) 2012 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/renderer/accessibility/accessibility_node_serializer.h"
 
 #include <set>
 
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ skipping 33 matching lines @@
   WebAXObject parent = child.parentObject();
   while (!parent.isDetached() && parent.accessibilityIsIgnored())
     parent = parent.parentObject();
   return parent.equals(ancestor);
 }
 
   bool IsTrue(std::string html_value) {
   return LowerCaseEqualsASCII(html_value, "true");
 }
 
+std::string GetEquivalentAriaRoleString(const ui::AXRole role) {
+  switch (role) {
+    case ui::AX_ROLE_ARTICLE:
+      return "article";
+    case ui::AX_ROLE_BANNER:
+      return "banner";
+    case ui::AX_ROLE_COMPLEMENTARY:
+      return "complementary";
+    case ui::AX_ROLE_CONTENT_INFO:
+    case ui::AX_ROLE_FOOTER:
+      return "contentinfo";
+    case ui::AX_ROLE_MAIN:
+      return "main";
+    case ui::AX_ROLE_NAVIGATION:
+      return "navigation";
+    case ui::AX_ROLE_REGION:
+      return "region";
+    default:
+      break;
+  }
+
+  return std::string();
+}
+
 }  // Anonymous namespace
 
 void SerializeAccessibilityNode(
     const WebAXObject& src,
     ui::AXNodeData* dst) {
   dst->role = AXRoleFromBlink(src.role());
   dst->state = AXStateFromBlink(src);
   dst->location = src.boundingBoxRect();
   dst->id = src.axID();
   std::string name = base::UTF16ToUTF8(src.title());
@@ skipping 131 matching lines @@
         for (size_t i = 0; i < src_line_breaks.size(); ++i)
           line_breaks.push_back(src_line_breaks[i]);
         dst->AddIntListAttribute(ui::AX_ATTR_LINE_BREAKS, line_breaks);
       }
     }
 
     // ARIA role.
     if (element.hasAttribute("role")) {
       dst->AddStringAttribute(ui::AX_ATTR_ROLE,
                               UTF16ToUTF8(element.getAttribute("role")));
+    } else {
+      std::string role = GetEquivalentAriaRoleString(dst->role);
+      if (!role.empty())
+        dst->AddStringAttribute(ui::AX_ATTR_ROLE, role);
     }
 
     // Live region attributes
     live_atomic = base::UTF16ToUTF8(element.getAttribute("aria-atomic"));
     live_busy = base::UTF16ToUTF8(element.getAttribute("aria-busy"));
     live_status = base::UTF16ToUTF8(element.getAttribute("aria-live"));
     live_relevant = base::UTF16ToUTF8(element.getAttribute("aria-relevant"));
   }
 
   // Walk up the parent chain to set live region attributes of containers
@@ skipping 193 matching lines @@
   WebNode node = parent.node();
   if (!node.isNull() && node.isElementNode()) {
     WebElement element = node.to<WebElement>();
     is_iframe = (element.tagName() == base::ASCIIToUTF16("IFRAME"));
   }
 
   return (is_iframe || IsParentUnignoredOf(parent, child));
 }
 
 }  // namespace content