Make RenderObject::style() return a const object

Source/core/layout/LayoutThemeChromiumSkia.h

Index: Source/core/layout/LayoutThemeChromiumSkia.h
diff --git a/Source/core/layout/LayoutThemeChromiumSkia.h b/Source/core/layout/LayoutThemeChromiumSkia.h
index a15730db8efa842946f32c9a2e66e87516fb3f23..830159ef103239f4f6e5b9d6fee27fd0d3ace69d 100644
--- a/Source/core/layout/LayoutThemeChromiumSkia.h
+++ b/Source/core/layout/LayoutThemeChromiumSkia.h
@@ -66,7 +66,7 @@ public:
     // System fonts.
     virtual void systemFont(CSSValueID systemFontID, FontStyle&, FontWeight&, float& fontSize, AtomicString& fontFamily) const;
 
-    virtual int minimumMenuListSize(RenderStyle*) const override;
+    virtual int minimumMenuListSize(const RenderStyle*) const override;
 
     virtual void setCheckboxSize(RenderStyle*) const override;
 
@@ -118,10 +118,10 @@ public:
     virtual double animationDurationForProgressBar(RenderProgress*) const override;
 
     // These methods define the padding for the MenuList's inner block.
-    virtual int popupInternalPaddingLeft(RenderStyle*) const override;
-    virtual int popupInternalPaddingRight(RenderStyle*) const override;
-    virtual int popupInternalPaddingTop(RenderStyle*) const override;
-    virtual int popupInternalPaddingBottom(RenderStyle*) const override;
+    virtual int popupInternalPaddingLeft(const RenderStyle*) const override;
+    virtual int popupInternalPaddingRight(const RenderStyle*) const override;
+    virtual int popupInternalPaddingTop(const RenderStyle*) const override;
+    virtual int popupInternalPaddingBottom(const RenderStyle*) const override;
 
     // Provide a way to pass the default font size from the Settings object
     // to the render theme. FIXME: http://b/1129186 A cleaner way would be
@@ -152,7 +152,7 @@ protected:
 private:
     virtual bool shouldShowPlaceholderWhenFocused() const override;
 
-    int menuListInternalPadding(RenderStyle*, int paddingType) const;
+    int menuListInternalPadding(const RenderStyle*, int paddingType) const;
     bool paintMediaButtonInternal(GraphicsContext*, const IntRect&, Image*);
     IntRect convertToPaintingRect(RenderObject* inputRenderer, const RenderObject* partRenderer, LayoutRect partRect, const IntRect& localOffset) const;