INPUT element: Updating value to the previous defaultValue should dispatch "change" event.

third_party/WebKit/Source/core/html/HTMLInputElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
  * rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved.
@@ skipping 700 matching lines @@
   } else if (name == typeAttr) {
     updateType();
   } else if (name == valueAttr) {
     // We only need to setChanged if the form is looking at the default value
     // right now.
     if (!hasDirtyValue()) {
       updatePlaceholderVisibility();
       setNeedsStyleRecalc(
           SubtreeStyleChange,
           StyleChangeReasonForTracing::fromAttribute(valueAttr));
+      if (m_inputType->valueMode() == ValueMode::kValue)
+        setTextAsOfLastFormControlChangeEvent(sanitizeValue(value));
     }
     m_needsToUpdateViewValue = true;
     setNeedsValidityCheck();
     m_valueAttributeWasUpdatedAfterParsing = !m_parsingInProgress;
     m_inputType->warnIfValueIsInvalidAndElementIsVisible(value);
     m_inputTypeView->valueAttributeChanged();
   } else if (name == checkedAttr) {
     // Another radio button in the same group might be checked by state
     // restore. We shouldn't call setChecked() even if this has the checked
     // attribute. So, delay the setChecked() call until
@@ skipping 1200 matching lines @@
 
 bool HTMLInputElement::hasFallbackContent() const {
   return m_inputTypeView->hasFallbackContent();
 }
 
 void HTMLInputElement::setFilesFromPaths(const Vector<String>& paths) {
   return m_inputType->setFilesFromPaths(paths);
 }
 
 }  // namespace blink