Make RenderObject::style() return a const object

Source/core/rendering/RenderCombineText.cpp

Index: Source/core/rendering/RenderCombineText.cpp
diff --git a/Source/core/rendering/RenderCombineText.cpp b/Source/core/rendering/RenderCombineText.cpp
index e911b1f95afd40ed7494d61e61487483501e1ce8..4e751985ea552ffa45f3e39eaba2fe2e5f3af550 100644
--- a/Source/core/rendering/RenderCombineText.cpp
+++ b/Source/core/rendering/RenderCombineText.cpp
@@ -125,7 +125,7 @@ void RenderCombineText::updateFont()
 
     FontSelector* fontSelector = style()->font().fontSelector();
 
-    bool shouldUpdateFont = style()->setFontDescription(description); // Need to change font orientation to horizontal.
+    bool shouldUpdateFont = mutableStyleRef().setFontDescription(description); // Need to change font orientation to horizontal.
 
     if (m_combinedTextWidth <= emWidth) {
         m_scaleX = 1.0f;
@@ -141,7 +141,7 @@ void RenderCombineText::updateFont()
                 m_combinedTextWidth = runWidth;
 
                 // Replace my font with the new one.
-                shouldUpdateFont = style()->setFontDescription(description);
+                shouldUpdateFont = mutableStyleRef().setFontDescription(description);
                 break;
             }
         }