Re-land: Send Windows accessibility events based on tree updates.

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/i18n/break_iterator.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 312 matching lines @@
       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.
 
   // First, always return the |value| attribute if this is an
   // input field.
-  if (!value().empty()) {
+  base::string16 value = GetString16Attribute(ui::AX_ATTR_VALUE);
+  if (!value.empty()) {
     if (HasState(ui::AX_STATE_EDITABLE))
-      return base::UTF8ToUTF16(value());
+      return value;
 
     switch (GetRole()) {
       case ui::AX_ROLE_COMBO_BOX:
       case ui::AX_ROLE_POP_UP_BUTTON:
       case ui::AX_ROLE_TEXT_AREA:
       case ui::AX_ROLE_TEXT_FIELD:
-        return base::UTF8ToUTF16(value());
+        return value;
     }
   }
 
   // For color wells, the color is stored in separate attributes.
   // Perhaps we could return color names in the future?
   if (GetRole() == ui::AX_ROLE_COLOR_WELL) {
     int red = GetIntAttribute(ui::AX_ATTR_COLOR_VALUE_RED);
     int green = GetIntAttribute(ui::AX_ATTR_COLOR_VALUE_GREEN);
     int blue = GetIntAttribute(ui::AX_ATTR_COLOR_VALUE_BLUE);
     return base::UTF8ToUTF16(
         base::StringPrintf("#%02X%02X%02X", red, green, blue));
   }
 
   // Always prefer visible text if this is a link. Sites sometimes add
   // a "title" attribute to a link with more information, but we can't
   // lose the link text.
-  if (!name().empty() && GetRole() == ui::AX_ROLE_LINK)
-    return base::UTF8ToUTF16(name());
+  base::string16 name = GetString16Attribute(ui::AX_ATTR_NAME);
+  if (!name.empty() && GetRole() == ui::AX_ROLE_LINK)
+    return name;
 
   // If there's no text value, 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);
 
   base::string16 placeholder;
   switch (GetRole()) {
     case ui::AX_ROLE_DATE:
     case ui::AX_ROLE_TEXT_AREA:
     case ui::AX_ROLE_TEXT_FIELD:
     case ui::AX_ROLE_TIME:
       GetHtmlAttribute("placeholder", &placeholder);
   }
 
   int title_elem_id = GetIntAttribute(
       ui::AX_ATTR_TITLE_UI_ELEMENT);
   base::string16 text;
   if (!description.empty())
     text = description;
-  else if (title_elem_id && !name().empty())
-    text = base::UTF8ToUTF16(name());
+  else if (title_elem_id && !name.empty())
+    text = name;
   else if (!help.empty())
     text = help;
-  else if (!name().empty())
-    text = base::UTF8ToUTF16(name());
+  else if (!name.empty())
+    text = name;
   else if (!placeholder.empty())
     text = placeholder;
-  else if (!value().empty())
-    text = base::UTF8ToUTF16(value());
+  else if (!value.empty())
+    text = value;
   else if (title_elem_id) {
     BrowserAccessibility* title_elem =
           manager()->GetFromID(title_elem_id);
     if (title_elem)
       text = static_cast<BrowserAccessibilityAndroid*>(title_elem)->GetText();
   }
 
   // This is called from PlatformIsLeaf, so don't call PlatformChildCount
   // from within this!
   if (text.empty() &&
@@ skipping 150 matching lines @@
   return sel_start;
 }
 
 int BrowserAccessibilityAndroid::GetSelectionEnd() const {
   int sel_end = 0;
   GetIntAttribute(ui::AX_ATTR_TEXT_SEL_END, &sel_end);
   return sel_end;
 }
 
 int BrowserAccessibilityAndroid::GetEditableTextLength() const {
-  return value().length();
+  base::string16 value = GetString16Attribute(ui::AX_ATTR_VALUE);
+  return value.length();
 }
 
 int BrowserAccessibilityAndroid::AndroidInputType() const {
   std::string html_tag = GetStringAttribute(
       ui::AX_ATTR_HTML_TAG);
   if (html_tag != "input")
     return ANDROID_TEXT_INPUTTYPE_TYPE_NULL;
 
   std::string type;
   if (!GetHtmlAttribute("type", &type))
@@ skipping 247 matching lines @@
 bool BrowserAccessibilityAndroid::IsIframe() const {
   base::string16 html_tag = GetString16Attribute(
       ui::AX_ATTR_HTML_TAG);
   return html_tag == base::ASCIIToUTF16("iframe");
 }
 
 void BrowserAccessibilityAndroid::OnDataChanged() {
   BrowserAccessibility::OnDataChanged();
 
   if (IsEditableText()) {
-    if (base::UTF8ToUTF16(value()) != new_value_) {
+    base::string16 value = GetString16Attribute(ui::AX_ATTR_VALUE);
+    if (value != new_value_) {
       old_value_ = new_value_;
-      new_value_ = base::UTF8ToUTF16(value());
+      new_value_ = value;
     }
   }
 
   if (GetRole() == ui::AX_ROLE_ALERT && first_time_)
     manager()->NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, this);
 
   base::string16 live;
   if (GetString16Attribute(
       ui::AX_ATTR_CONTAINER_LIVE_STATUS, &live)) {
     NotifyLiveRegionUpdate(live);
@@ skipping 21 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