Remove unused includes from core/html .cpp files

Source/core/html/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 15 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * 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 "config.h"
 #include "core/html/BaseButtonInputType.h"
 
 #include "HTMLNames.h"
-#include "core/dom/KeyboardEvent.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/rendering/RenderButton.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 bool BaseButtonInputType::shouldSaveAndRestoreFormControlState() const
 {
     return false;
@@ skipping 14 matching lines @@
 {
     return false;
 }
 
 void BaseButtonInputType::setValue(const String& sanitizedValue, bool, TextFieldEventBehavior)
 {
     element()->setAttribute(valueAttr, sanitizedValue);
 }
 
 } // namespace WebCore