Fix the crash of issue 2209773002

third_party/WebKit/Source/core/layout/LayoutTheme.cpp

 /**
  * This file is part of the theme implementation for form controls in WebCore.
  *
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 617 matching lines @@
 {
     return inputElement->isSteppable() && inputElement->type() != InputTypeNames::range;
 }
 
 void LayoutTheme::adjustMenuListButtonStyle(ComputedStyle&, Element*) const
 {
 }
 
 void LayoutTheme::adjustSliderContainerStyle(ComputedStyle& style, Element* e) const
 {
-    if (e->shadowPseudoId() == "-webkit-media-slider-container" || e->shadowPseudoId() == "-webkit-slider-container") {
+    if (e && (e->shadowPseudoId() == "-webkit-media-slider-container" || e->shadowPseudoId() == "-webkit-slider-container")) {
         if (style.appearance() == SliderVerticalPart) {
             style.setTouchAction(TouchActionPanX);
             style.setAppearance(NoControlPart);
         } else {
             style.setTouchAction(TouchActionPanY);
             style.setAppearance(NoControlPart);
         }
     }
 }
 
@@ skipping 284 matching lines @@
 
     // padding - not honored by WinIE, needs to be removed.
     style.resetPadding();
 
     // border - honored by WinIE, but looks terrible (just paints in the control box and turns off the Windows XP theme)
     // for now, we will not honor it.
     style.resetBorder();
 }
 
 } // namespace blink