Resubmission of sashab's patch: Make CSSComputedStyledeclaration::getPropertyCSSValue return const

third_party/WebKit/Source/core/css/cssom/ComputedStylePropertyMap.cpp

 // Copyright 2016 the Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/css/cssom/ComputedStylePropertyMap.h"
 
 #include "core/css/CSSComputedStyleDeclaration.h"
 #include "core/css/cssom/StyleValueFactory.h"
 
 namespace blink {
 
 StylePropertyMap::StyleValueVector ComputedStylePropertyMap::getAll(CSSPropertyID propertyID)
 {
-    CSSValue* cssValue = m_computedStyleDeclaration->getPropertyCSSValueInternal(propertyID);
+    const CSSValue* cssValue = m_computedStyleDeclaration->getPropertyCSSValueInternal(propertyID);
     if (!cssValue)
         return StylePropertyMap::StyleValueVector();
     return cssValueToStyleValueVector(propertyID, *cssValue);
 }
 
 Vector<String> ComputedStylePropertyMap::getProperties()
 {
     Vector<String> result;
     for (unsigned i = 0; i < m_computedStyleDeclaration->length(); i++) {
         result.append(m_computedStyleDeclaration->item(i));
     }
     return result;
 }
 
 } // namespace blink