Make RenderObject::style() return a const object

Source/modules/accessibility/AXRenderObject.cpp

 /*
 * Copyright (C) 2008 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:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 796 matching lines @@
         axorientation = AccessibilityOrientationVertical;
     return axorientation;
 }
 
 String AXRenderObject::text() const
 {
     if (isPasswordFieldAndShouldHideValue()) {
         if (!m_renderer)
             return String();
 
-        LayoutStyle* style = m_renderer->style();
+        const LayoutStyle* style = m_renderer->style();
         if (!style)
             return String();
 
         unsigned unmaskedTextLength = AXNodeObject::text().length();
         if (!unmaskedTextLength)
             return String();
 
         UChar maskCharacter = 0;
         switch (style->textSecurity()) {
         case TSNONE:
@@ skipping 1583 matching lines @@
         if (label && label->renderer()) {
             LayoutRect labelRect = axObjectCache()->getOrCreate(label)->elementRect();
             result.unite(labelRect);
         }
     }
 
     return result;
 }
 
 } // namespace blink