Make RenderObject::style() return a const object

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * 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 179 matching lines @@
             imageResources.append(styleImage->cachedImage());
     }
 }
 
 static void appendLayers(Vector<ImageResource*>& images, const FillLayer& styleLayer)
 {
     for (const FillLayer* layer = &styleLayer; layer; layer = layer->next())
         appendImageIfNotNull(images, layer->image());
 }
 
-static void appendImagesFromStyle(Vector<ImageResource*>& images, RenderStyle& blockStyle)
+static void appendImagesFromStyle(Vector<ImageResource*>& images, const RenderStyle& blockStyle)
 {
     appendLayers(images, blockStyle.backgroundLayers());
     appendLayers(images, blockStyle.maskLayers());
 
     const ContentData* contentData = blockStyle.contentData();
     if (contentData && contentData->isImage())
         appendImageIfNotNull(images, toImageContentData(contentData)->image());
     if (blockStyle.boxReflect())
         appendImageIfNotNull(images, blockStyle.boxReflect()->mask().image());
     appendImageIfNotNull(images, blockStyle.listStyleImage());
@@ skipping 75 matching lines @@
         gDelayedUpdateScrollInfoSet->remove(this);
 
     if (TextAutosizer* textAutosizer = document().textAutosizer())
         textAutosizer->destroy(this);
 
     RenderBox::willBeDestroyed();
 }
 
 void RenderBlock::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
 {
-    RenderStyle* oldStyle = style();
+    const RenderStyle* oldStyle = style();
 
     setReplaced(newStyle.isDisplayInlineType());
 
     if (oldStyle && parent()) {
         bool oldStyleIsContainer = oldStyle->position() != StaticPosition || oldStyle->hasTransformRelatedProperty();
         bool newStyleIsContainer = newStyle.position() != StaticPosition || newStyle.hasTransformRelatedProperty();
 
         if (oldStyleIsContainer && !newStyleIsContainer) {
             // Clear our positioned objects list. Our absolutely positioned descendants will be
             // inserted into our containing block's positioned objects list during layout.
@@ skipping 32 matching lines @@
         || oldStyle->paddingBottom() != newStyle->paddingBottom();
 }
 
 void RenderBlock::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
 {
     RenderBox::styleDidChange(diff, oldStyle);
 
     if (isFloatingOrOutOfFlowPositioned() && oldStyle && !oldStyle->isFloating() && !oldStyle->hasOutOfFlowPosition() && parent() && parent()->isRenderBlockFlow())
         toRenderBlock(parent())->removeAnonymousWrappersIfRequired();
 
-    RenderStyle* newStyle = style();
+    RenderStyle* newStyle = deprecatedMutableStyle();
 
     if (!isAnonymousBlock()) {
         // Ensure that all of our continuation blocks pick up the new style.
         for (RenderBlock* currCont = blockElementContinuation(); currCont; currCont = currCont->blockElementContinuation()) {
             RenderBoxModelObject* nextCont = currCont->continuation();
             currCont->setContinuation(0);
             currCont->setStyle(newStyle);
             currCont->setContinuation(nextCont);
         }
     }
@@ skipping 224 matching lines @@
 RenderBlock* RenderBlock::clone() const
 {
     RenderBlock* cloneBlock;
     if (isAnonymousBlock()) {
         cloneBlock = createAnonymousBlock();
         cloneBlock->setChildrenInline(childrenInline());
     }
     else {
         RenderObject* cloneRenderer = toElement(node())->createRenderer(style());
         cloneBlock = toRenderBlock(cloneRenderer);
-        cloneBlock->setStyle(style());
+        cloneBlock->setStyle(deprecatedMutableStyle());
 
         // This takes care of setting the right value of childrenInline in case
         // generated content is added to cloneBlock and 'this' does not have
         // generated content added yet.
         cloneBlock->setChildrenInline(cloneBlock->firstChild() ? cloneBlock->firstChild()->isInline() : childrenInline());
     }
     cloneBlock->setFlowThreadState(flowThreadState());
     return cloneBlock;
 }
 
@@ skipping 2370 matching lines @@
 
 void RenderBlock::computePreferredLogicalWidths()
 {
     ASSERT(preferredLogicalWidthsDirty());
 
     m_minPreferredLogicalWidth = 0;
     m_maxPreferredLogicalWidth = 0;
 
     // FIXME: The isFixed() calls here should probably be checking for isSpecified since you
     // should be able to use percentage, calc or viewport relative values for width.
-    RenderStyle* styleToUse = style();
+    const RenderStyle* styleToUse = style();
     if (!isTableCell() && styleToUse->logicalWidth().isFixed() && styleToUse->logicalWidth().value() >= 0
         && !(isDeprecatedFlexItem() && !styleToUse->logicalWidth().intValue()))
         m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalWidth().value());
     else
         computeIntrinsicLogicalWidths(m_minPreferredLogicalWidth, m_maxPreferredLogicalWidth);
 
     if (styleToUse->logicalMinWidth().isFixed() && styleToUse->logicalMinWidth().value() > 0) {
         m_maxPreferredLogicalWidth = std::max(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMinWidth().value()));
         m_minPreferredLogicalWidth = std::max(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse->logicalMinWidth().value()));
     }
@@ skipping 36 matching lines @@
         // intrinsic width, instead of pretending that it's 1. The only way to do that is by
         // performing a layout pass, but this is not an appropriate time or place for layout. The
         // good news is that if height is unconstrained and there are no explicit breaks, the
         // resolved column-count really should be 1.
         maxLogicalWidth = std::max(maxLogicalWidth, columnWidth) * columnCount + gapExtra;
     }
 }
 
 void RenderBlock::computeBlockPreferredLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
 {
-    RenderStyle* styleToUse = style();
+    const RenderStyle* styleToUse = style();
     bool nowrap = styleToUse->whiteSpace() == NOWRAP;
 
     RenderObject* child = firstChild();
     RenderBlock* containingBlock = this->containingBlock();
     LayoutUnit floatLeftWidth = 0, floatRightWidth = 0;
     while (child) {
         // Positioned children don't affect the min/max width. Spanners only affect the min/max
         // width of the multicol container, not the flow thread.
         if (child->isOutOfFlowPositioned() || child->isColumnSpanAll()) {
             child = child->nextSibling();
             continue;
         }
 
-        RefPtr<RenderStyle> childStyle = child->style();
+        const RenderStyle* childStyle = child->style();
         if (child->isFloating() || (child->isBox() && toRenderBox(child)->avoidsFloats())) {
             LayoutUnit floatTotalWidth = floatLeftWidth + floatRightWidth;
             if (childStyle->clear() & CLEFT) {
                 maxLogicalWidth = std::max(floatTotalWidth, maxLogicalWidth);
                 floatLeftWidth = 0;
             }
             if (childStyle->clear() & CRIGHT) {
                 maxLogicalWidth = std::max(floatTotalWidth, maxLogicalWidth);
                 floatRightWidth = 0;
             }
@@ skipping 86 matching lines @@
 
 LayoutUnit RenderBlock::lineHeight(bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const
 {
     // Inline blocks are replaced elements. Otherwise, just pass off to
     // the base class.  If we're being queried as though we're the root line
     // box, then the fact that we're an inline-block is irrelevant, and we behave
     // just like a block.
     if (isReplaced() && linePositionMode == PositionOnContainingLine)
         return RenderBox::lineHeight(firstLine, direction, linePositionMode);
 
-    RenderStyle* s = style(firstLine && document().styleEngine()->usesFirstLineRules());
+    const RenderStyle* s = style(firstLine && document().styleEngine()->usesFirstLineRules());
     return s->computedLineHeight();
 }
 
 int RenderBlock::beforeMarginInLineDirection(LineDirectionMode direction) const
 {
     return direction == HorizontalLine ? marginTop() : marginRight();
 }
 
 int RenderBlock::baselinePosition(FontBaseline baselineType, bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const
 {
@@ skipping 607 matching lines @@
 
     RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parent->style(), newDisplay);
     parent->updateAnonymousChildStyle(newBox, newStyle.get());
     newBox->setStyle(newStyle.release());
     return newBox;
 }
 
 RenderBlockFlow* RenderBlock::createAnonymousColumnsWithParentRenderer(const RenderObject* parent)
 {
     RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parent->style(), BLOCK);
-    newStyle->inheritColumnPropertiesFrom(parent->style());
+    newStyle->inheritColumnPropertiesFrom(*parent->style());
 
     RenderBlockFlow* newBox = RenderBlockFlow::createAnonymous(&parent->document());
     parent->updateAnonymousChildStyle(newBox, newStyle.get());
     newBox->setStyle(newStyle.release());
     return newBox;
 }
 
 RenderBlockFlow* RenderBlock::createAnonymousColumnSpanWithParentRenderer(const RenderObject* parent)
 {
     RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parent->style(), BLOCK);
@@ skipping 145 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink