Do not cache the result of RenderStyle::computedLineHeight()

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 137 matching lines @@
 
 private:
     const RenderBlock* m_block;
     bool m_shouldDispatchEvent;
     bool m_hadHorizontalLayoutOverflow;
     bool m_hadVerticalLayoutOverflow;
 };
 
 RenderBlock::RenderBlock(ContainerNode* node)
     : RenderBox(node)
-    , m_lineHeight(-1)
     , m_hasMarginBeforeQuirk(false)
     , m_hasMarginAfterQuirk(false)
     , m_beingDestroyed(false)
     , m_hasMarkupTruncation(false)
     , m_hasBorderOrPaddingLogicalWidthChanged(false)
     , m_hasOnlySelfCollapsingChildren(false)
 {
     setChildrenInline(true);
 }
 
@@ skipping 175 matching lines @@
             currCont->setContinuation(0);
             currCont->setStyle(newStyle);
             currCont->setContinuation(nextCont);
         }
     }
 
     if (FastTextAutosizer* textAutosizer = document().fastTextAutosizer())
         textAutosizer->record(this);
 
     propagateStyleToAnonymousChildren(true);
-    invalidateLineHeight();
 
     // It's possible for our border/padding to change, but for the overall logical width of the block to
     // end up being the same. We keep track of this change so in layoutBlock, we can know to set relayoutChildren=true.
     m_hasBorderOrPaddingLogicalWidthChanged = oldStyle && diff.needsFullLayout() && needsLayout() && borderOrPaddingLogicalWidthChanged(oldStyle, newStyle);
 
     // If the style has unloaded images, want to notify the ResourceLoadPriorityOptimizer so that
     // network priorities can be set.
     Vector<ImageResource*> images;
     appendImagesFromStyle(images, *newStyle);
     if (images.isEmpty())
@@ skipping 3412 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);
 
-    if (firstLine && document().styleEngine()->usesFirstLineRules()) {
-        RenderStyle* s = style(firstLine);
-        if (s != style())
-            return s->computedLineHeight();
-    }
-
-    if (m_lineHeight == -1)
-        m_lineHeight = style()->computedLineHeight();
-
-    return m_lineHeight;
+    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
 {
     // Inline blocks are replaced elements. Otherwise, just pass off to
@@ skipping 1240 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 WebCore