Do not dispatch 'change' events during pressing spin buttons for input[type=number].

Source/core/html/forms/TextFieldInputType.cpp

Index: Source/core/html/forms/TextFieldInputType.cpp
diff --git a/Source/core/html/forms/TextFieldInputType.cpp b/Source/core/html/forms/TextFieldInputType.cpp
index 041d0307d823880aa98a8326103e359f9742e37a..4b03d211796c6000a83c1e97a066e5a2d5e9271f 100644
--- a/Source/core/html/forms/TextFieldInputType.cpp
+++ b/Source/core/html/forms/TextFieldInputType.cpp
@@ -212,6 +212,7 @@ void TextFieldInputType::handleKeydownEventForSpinButton(KeyboardEvent* event)
         spinButtonStepDown();
     else
         return;
+    element().dispatchFormControlChangeEvent();
     event->setDefaultHandled();
 }
 
@@ -254,6 +255,8 @@ void TextFieldInputType::handleBlurEvent()
 {
     InputType::handleBlurEvent();
     element().endEditing();
+    if (SpinButtonElement *spinButton = spinButtonElement())
+        spinButton->releaseCapture();
 }
 
 bool TextFieldInputType::shouldSubmitImplicitly(Event* event)
@@ -558,4 +561,9 @@ bool TextFieldInputType::shouldSpinButtonRespondToWheelEvents()
     return shouldSpinButtonRespondToMouseEvents() && element().focused();
 }
 
+void TextFieldInputType::spinButtonDidReleaseMouseCapture()
+{
+    element().dispatchFormControlChangeEvent();
+}
+
 } // namespace WebCore