Merge 140324

Source/WebCore/html/BaseMultipleFieldsDateAndTimeInputType.cpp

 /*
  * Copyright (C) 2010 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 55 matching lines @@
     // We don't need to call focus(). This function is called when control
     // got focus.
 
     // Add focus ring by CSS "focus" pseudo class.
     element()->setFocus(true);
 }
 
 void BaseMultipleFieldsDateAndTimeInputType::editControlValueChanged()
 {
     RefPtr<HTMLInputElement> input(element());
-    input->setValueInternal(sanitizeValue(m_dateTimeEditElement->value()), DispatchNoEvent);
-    input->setNeedsStyleRecalc();
-    input->dispatchFormControlInputEvent();
-    input->dispatchFormControlChangeEvent();
+    String oldValue = input->value();
+    String newValue = sanitizeValue(m_dateTimeEditElement->value());
+    // Even if oldValue is null and newValue is "", we should assume they are same.
+    if ((oldValue.isEmpty() && newValue.isEmpty()) || oldValue == newValue)
+        input->setNeedsValidityCheck();
+    else {
+        input->setValueInternal(newValue, DispatchNoEvent);
+        input->setNeedsStyleRecalc();
+        input->dispatchFormControlInputEvent();
+        input->dispatchFormControlChangeEvent();
+    }
     input->notifyFormStateChanged();
 }
 
 bool BaseMultipleFieldsDateAndTimeInputType::hasCustomFocusLogic() const
 {
     return false;
 }
 
 bool BaseMultipleFieldsDateAndTimeInputType::isEditControlOwnerDisabled() const
 {
@@ skipping 344 matching lines @@
 {
     StepRange stepRange = createStepRange(AnyIsDefaultStep);
     return date.second() || date.millisecond()
         || !stepRange.minimum().remainder(static_cast<int>(msPerMinute)).isZero()
         || !stepRange.step().remainder(static_cast<int>(msPerMinute)).isZero();
 }
 
 } // namespace WebCore
 
 #endif