More precise use of multiline state

third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp

 /*
  * Copyright (C) 2012, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 774 matching lines @@
       // Only aria-labelledby and aria-describedby can target hidden elements.
       if (child->AccessibilityIsIgnored() && attr != aria_labelledbyAttr &&
           attr != aria_labeledbyAttr && attr != aria_describedbyAttr) {
         continue;
       }
       children.push_back(child);
     }
   }
 }
 
+bool AXNodeObject::IsMultiline() const {
+  Node* node = this->GetNode();
+  if (!node)
+    return false;
+
+  const AccessibilityRole role = RoleValue();
+  const bool is_edit_box = role == kSearchBoxRole || role == kTextFieldRole;
+  if (!IsEditable() && !is_edit_box)
+    return false;  // Doesn't support multiline.
+
+  // Supports aria-multiline, so check for attribute.
+  bool is_multiline = false;
+  if (HasAOMPropertyOrARIAAttribute(AOMBooleanProperty::kMultiline,
+                                    is_multiline)) {
+    return is_multiline;
+  }
+
+  // Default for <textarea> is true.
+  if (isHTMLTextAreaElement(*node))
+    return true;
+
+  // Default for other edit boxes is false, including for ARIA, says CORE-AAM.
+  if (is_edit_box)
+    return false;
+
+  // If root of contenteditable area and no ARIA role of textbox/searchbox used,
+  // default to multiline=true which is what the default behavior is.
+  return HasContentEditableAttributeSet();
+}
+
 // This only returns true if this is the element that actually has the
 // contentEditable attribute set, unlike node->hasEditableStyle() which will
 // also return true if an ancestor is editable.
 bool AXNodeObject::HasContentEditableAttributeSet() const {
   const AtomicString& content_editable_value =
       GetAttribute(contenteditableAttr);
   if (content_editable_value.IsNull())
     return false;
   // Both "true" (case-insensitive) and the empty string count as true.
   return content_editable_value.IsEmpty() ||
          EqualIgnoringASCIICase(content_editable_value, "true");
 }
 
+// TODO(aleventhal) Find a more appropriate name or consider returning false
+// for everything but a searchbox or textfield, as a combobox and spinbox
+// can contain a field but should not be considered edit controls themselves.
 bool AXNodeObject::IsTextControl() const {
   if (HasContentEditableAttributeSet())
     return true;
 
   switch (RoleValue()) {
     case kTextFieldRole:
     case kComboBoxRole:
     case kSearchBoxRole:
     case kSpinButtonRole:
       return true;
@@ skipping 2440 matching lines @@
     return String();
   return ToTextControlElement(node)->StrippedPlaceholder();
 }
 
 DEFINE_TRACE(AXNodeObject) {
   visitor->Trace(node_);
   AXObject::Trace(visitor);
 }
 
 }  // namespace blink