Make RenderObject::style() return a const object

Source/core/rendering/style/RenderStyle.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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
@@ skipping 240 matching lines @@
         mutable unsigned hasViewportUnits : 1;
 
         // 32 bits
 
         unsigned pageBreakBefore : 2; // EPageBreak
         unsigned pageBreakAfter : 2; // EPageBreak
         unsigned pageBreakInside : 2; // EPageBreak
 
         unsigned styleType : 6; // PseudoId
         unsigned pseudoBits : 8;
-        unsigned explicitInheritance : 1; // Explicitly inherits a non-inherited property
-        unsigned unique : 1; // Style can not be shared.
+        // FIXME: This should be moved to ElementRateData.

[rune, 2015/01/29 23:16:32]

ElementRareData.

[Julien - ping for review, 2015/02/10 07:33:19]

Done.

+        mutable unsigned explicitInheritance : 1; // Explicitly inherits a non-inherited property
+        mutable unsigned unique : 1; // Style can not be shared.
 
         unsigned emptyState : 1;
 
         unsigned affectedByFocus : 1;
         unsigned affectedByHover : 1;
         unsigned affectedByActive : 1;
         unsigned affectedByDrag : 1;
 
         unsigned isLink : 1;
         // If you add more style bits here, you will also need to update RenderStyle::copyNonInheritedFrom()
@@ skipping 604 matching lines @@
     bool hasPerspective() const { return rareNonInheritedData->m_perspective > 0; }
     const LengthPoint& perspectiveOrigin() const { return rareNonInheritedData->m_perspectiveOrigin; }
     const Length& perspectiveOriginX() const { return perspectiveOrigin().x(); }
     const Length& perspectiveOriginY() const { return perspectiveOrigin().y(); }
     const LengthSize& pageSize() const { return rareNonInheritedData->m_pageSize; }
     PageSizeType pageSizeType() const { return static_cast<PageSizeType>(rareNonInheritedData->m_pageSizeType); }
 
     bool hasCurrentOpacityAnimation() const { return rareNonInheritedData->m_hasCurrentOpacityAnimation; }
     bool hasCurrentTransformAnimation() const { return rareNonInheritedData->m_hasCurrentTransformAnimation; }
     bool hasCurrentFilterAnimation() const { return rareNonInheritedData->m_hasCurrentFilterAnimation; }
-    bool shouldCompositeForCurrentAnimations() { return hasCurrentOpacityAnimation() || hasCurrentTransformAnimation() || hasCurrentFilterAnimation(); }
+    bool shouldCompositeForCurrentAnimations() const { return hasCurrentOpacityAnimation() || hasCurrentTransformAnimation() || hasCurrentFilterAnimation(); }
 
     bool isRunningOpacityAnimationOnCompositor() const { return rareNonInheritedData->m_runningOpacityAnimationOnCompositor; }
     bool isRunningTransformAnimationOnCompositor() const { return rareNonInheritedData->m_runningTransformAnimationOnCompositor; }
     bool isRunningFilterAnimationOnCompositor() const { return rareNonInheritedData->m_runningFilterAnimationOnCompositor; }
-    bool isRunningAnimationOnCompositor() { return isRunningOpacityAnimationOnCompositor() || isRunningTransformAnimationOnCompositor() || isRunningFilterAnimationOnCompositor(); }
+    bool isRunningAnimationOnCompositor() const { return isRunningOpacityAnimationOnCompositor() || isRunningTransformAnimationOnCompositor() || isRunningFilterAnimationOnCompositor(); }
 
     LineBoxContain lineBoxContain() const { return rareInheritedData->m_lineBoxContain; }
     const LineClampValue& lineClamp() const { return rareNonInheritedData->lineClamp; }
     Color tapHighlightColor() const { return rareInheritedData->tapHighlightColor; }
     ETextSecurity textSecurity() const { return static_cast<ETextSecurity>(rareInheritedData->textSecurity); }
 
     WritingMode writingMode() const { return static_cast<WritingMode>(inherited_flags.m_writingMode); }
     bool isHorizontalWritingMode() const { return blink::isHorizontalWritingMode(writingMode()); }
     bool isFlippedLinesWritingMode() const { return blink::isFlippedLinesWritingMode(writingMode()); }
     bool isFlippedBlocksWritingMode() const { return blink::isFlippedBlocksWritingMode(writingMode()); }
@@ skipping 366 matching lines @@
     void setColumnGap(float f) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_normalGap, false); SET_VAR(rareNonInheritedData.access()->m_multiCol, m_gap, f); }
     void setHasNormalColumnGap() { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_normalGap, true); SET_VAR(rareNonInheritedData.access()->m_multiCol, m_gap, 0); }
     void setColumnRuleColor(const StyleColor& c) { SET_BORDERVALUE_COLOR(rareNonInheritedData.access()->m_multiCol, m_rule, c); }
     void setColumnRuleStyle(EBorderStyle b) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_rule.m_style, b); }
     void setColumnRuleWidth(unsigned short w) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_rule.m_width, w); }
     void setColumnSpan(ColumnSpan columnSpan) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_columnSpan, columnSpan); }
     void setColumnBreakBefore(EPageBreak p) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_breakBefore, p); }
     // For valid values of column-break-inside see http://www.w3.org/TR/css3-multicol/#break-before-break-after-break-inside
     void setColumnBreakInside(EPageBreak p) { ASSERT(p == PBAUTO || p == PBAVOID); SET_VAR(rareNonInheritedData.access()->m_multiCol, m_breakInside, p); }
     void setColumnBreakAfter(EPageBreak p) { SET_VAR(rareNonInheritedData.access()->m_multiCol, m_breakAfter, p); }
-    void inheritColumnPropertiesFrom(RenderStyle* parent) { rareNonInheritedData.access()->m_multiCol = parent->rareNonInheritedData->m_multiCol; }
+    void inheritColumnPropertiesFrom(const RenderStyle& parent) { rareNonInheritedData.access()->m_multiCol = parent.rareNonInheritedData->m_multiCol; }
     void setHasInlineTransform(bool b) { SET_VAR(rareNonInheritedData, m_hasInlineTransform, b); }
     void setTransform(const TransformOperations& ops) { SET_VAR(rareNonInheritedData.access()->m_transform, m_operations, ops); }
     void setTransformOriginX(const Length& v) { setTransformOrigin(TransformOrigin(v, transformOriginY(), transformOriginZ())); }
     void setTransformOriginY(const Length& v) { setTransformOrigin(TransformOrigin(transformOriginX(), v, transformOriginZ())); }
     void setTransformOriginZ(float f) { setTransformOrigin(TransformOrigin(transformOriginX(), transformOriginY(), f)); }
     void setTransformOrigin(const TransformOrigin& o) { SET_VAR(rareNonInheritedData.access()->m_transform, m_origin, o); }
     void setSpeak(ESpeak s) { SET_VAR(rareInheritedData, speak, s); }
     void setTextCombine(TextCombine v) { SET_VAR(rareNonInheritedData, m_textCombine, v); }
     void setTextDecorationColor(const StyleColor& c) { SET_VAR(rareNonInheritedData, m_textDecorationColor, c); }
     void setTextEmphasisColor(const StyleColor& c) { SET_VAR_WITH_SETTER(rareInheritedData, textEmphasisColor, setTextEmphasisColor, c); }
@@ skipping 158 matching lines @@
     {
         if (v == writingMode())
             return false;
 
         inherited_flags.m_writingMode = v;
         return true;
     }
 
     // A unique style is one that has matches something that makes it impossible to share.
     bool unique() const { return noninherited_flags.unique; }
-    void setUnique() { noninherited_flags.unique = true; }
+    void setUnique() const { noninherited_flags.unique = true; }
 
     bool isSharable() const;
 
     bool emptyState() const { return noninherited_flags.emptyState; }
     void setEmptyState(bool b) { setUnique(); noninherited_flags.emptyState = b; }
 
     Color visitedDependentColor(int colorProperty) const;
 
-    void setHasExplicitlyInheritedProperties() { noninherited_flags.explicitInheritance = true; }
+    void setHasExplicitlyInheritedProperties() const { noninherited_flags.explicitInheritance = true; }
     bool hasExplicitlyInheritedProperties() const { return noninherited_flags.explicitInheritance; }
 
     bool hasBoxDecorations() const { return hasBorder() || hasBorderRadius() || hasOutline() || hasAppearance() || boxShadow() || hasFilter() || resize() != RESIZE_NONE; }
 
     bool borderObscuresBackground() const;
     void getBorderEdgeInfo(BorderEdge edges[], bool includeLogicalLeftEdge = true, bool includeLogicalRightEdge = true) const;
 
     // Initial values for all the properties
     static EBorderCollapse initialBorderCollapse() { return BSEPARATE; }
     static EBorderStyle initialBorderStyle() { return BNONE; }
@@ skipping 373 matching lines @@
 inline bool RenderStyle::hasPseudoElementStyle() const
 {
     return noninherited_flags.pseudoBits & PSEUDO_ELEMENT_MASK;
 }
 
 float calcBorderRadiiConstraintScaleFor(const FloatRect&, const FloatRoundedRect::Radii&);
 
 } // namespace blink
 
 #endif // RenderStyle_h