Remove unnecessary repaint from line layout and cleanup logic

Source/core/rendering/line/LineLayoutState.h

Index: Source/core/rendering/line/LineLayoutState.h
diff --git a/Source/core/rendering/line/LineLayoutState.h b/Source/core/rendering/line/LineLayoutState.h
index 963c515d4936dcdc1fc479d5666236504a9bd579..bc7480fcd61228277905942f3be1fe594bcbe756 100644
--- a/Source/core/rendering/line/LineLayoutState.h
+++ b/Source/core/rendering/line/LineLayoutState.h
@@ -42,6 +42,7 @@ public:
         , m_endLineLogicalTop(0)
         , m_endLineMatched(false)
         , m_checkForFloatsFromLastLine(false)
+        , m_hasInlineChild(false)
         , m_isFullLayout(fullLayout)
         , m_repaintLogicalTop(repaintLogicalTop)
         , m_repaintLogicalBottom(repaintLogicalBottom)
@@ -74,6 +75,9 @@ public:
     bool checkForFloatsFromLastLine() const { return m_checkForFloatsFromLastLine; }
     void setCheckForFloatsFromLastLine(bool check) { m_checkForFloatsFromLastLine = check; }
 
+    bool hasInlineChild() const { return m_hasInlineChild; }
+    void setHasInlineChild(bool hasInlineChild) { m_hasInlineChild = hasInlineChild; }
+
     LineInfo& lineInfo() { return m_lineInfo; }
     const LineInfo& lineInfo() const { return m_lineInfo; }
 
@@ -106,6 +110,9 @@ private:
     LayoutUnit m_endLineLogicalTop;
     bool m_endLineMatched;
     bool m_checkForFloatsFromLastLine;
+    // Used as a performance optimization to avoid doing a full repaint when our floats
+    // change but we don't have any inline children.
+    bool m_hasInlineChild;
 
     bool m_isFullLayout;