Option, checkbox and radio should support ':default' selector

third_party/WebKit/Source/core/html/forms/BaseButtonInputType.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2011 Apple 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 16 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/html/forms/BaseButtonInputType.h"
 
 #include "core/HTMLNames.h"
 #include "core/dom/Text.h"
 #include "core/dom/shadow/ShadowRoot.h"
+#include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/layout/LayoutButton.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 void BaseButtonInputType::createShadowSubtree()
 {
@@ skipping 28 matching lines @@
 bool BaseButtonInputType::storesValueSeparateFromAttribute()
 {
     return false;
 }
 
 void BaseButtonInputType::setValue(const String& sanitizedValue, bool, TextFieldEventBehavior)
 {
     element().setAttribute(valueAttr, AtomicString(sanitizedValue));
 }
 
+bool BaseButtonInputType::matchesDefaultPseudoClass()
+{
+    // HTMLFormElement::findDefaultButton() traverses the tree. So we check
+    // canBeSuccessfulSubmitButton() first for early return.
+    return canBeSuccessfulSubmitButton() && element().form() && element().form()->findDefaultButton() == &element();
+}
+
 } // namespace blink