Handling of different types of empty alt

content/browser/accessibility/browser_accessibility_cocoa.mm

 // 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.
 
 #import "content/browser/accessibility/browser_accessibility_cocoa.h"
 
 #include <execinfo.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
@@ skipping 842 matching lines @@
         nameFrom == ui::AX_NAME_FROM_VALUE) {
       return @"";
     } else {
       return base::SysUTF8ToNSString(name);
     }
   }
 
   // Given an image where there's no other title, return the base part
   // of the filename as the description.
   if ([[self role] isEqualToString:NSAccessibilityImageRole]) {
-    if (browserAccessibility_->HasStringAttribute(ui::AX_ATTR_NAME))
+    if (browserAccessibility_->HasExplicitlyEmptyName())

[aleventhal, 2017/05/01 17:33:17]

We already checked for empty AX_ATTR_NAME above and returned already if not
empty.

       return @"";
     if ([self titleUIElement])
       return @"";
 
     std::string url;
     if (browserAccessibility_->GetStringAttribute(
             ui::AX_ATTR_URL, &url)) {
       // Given a url like http://foo.com/bar/baz.png, just return the
       // base name, e.g., "baz.png".
       size_t leftIndex = url.rfind('/');
@@ skipping 2026 matching lines @@
 }
 
 - (BOOL)accessibilityNotifiesWhenDestroyed {
   // Indicate that BrowserAccessibilityCocoa will post a notification when it's
   // destroyed (see -detach). This allows VoiceOver to do some internal things
   // more efficiently.
   return YES;
 }
 
 @end